Indaptus Therapeutics Inc.

07/08/2024 | Press release | Distributed by Public on 07/08/2024 21:29

Supplemental Prospectus - Form 424B5

As filed Pursuant to Rule 424(b)(5)

Registration No. 333-267236

PROSPECTUS SUPPLEMENT

(To Prospectus dated September 9, 2022)

Indaptus Therapeutics, Inc.

1,643,837 Shares of Common Stock

We are offering 1,643,837 shares of our common stock, par value $0.01 per share ("common stock") in a registered direct offering pursuant to this prospectus supplement and the accompanying prospectus and a securities purchase agreement, dated August 7, 2024, by and between the Company and certain accredited and institutional investors (the "Purchase Agreement").

In a concurrent private placement, we are also selling to such investors unregistered warrants to purchase up to an aggregate of 1,643,837 shares of our common stock (the "PIPE Warrants"). Each PIPE Warrant will be exercisable for one share of our common stock (the "PIPE Warrant Shares") at an exercise price of $1.70 per share and will have a term of five years from the date of issuance. The PIPE Warrants and the PIPE Warrant Shares are not being registered under the Securities Act of 1933, as amended (the "Securities Act"), and are being offered pursuant to the exemptions provided in Section 4(a)(2) under the Securities Act, and Rule 506(b) promulgated thereunder, and are not being offered pursuant to this prospectus supplement and the accompanying prospectus.

We are offering 1,643,837 shares of our common stock and accompanying PIPE Warrants in a concurrent private placement to investors at a combined offering price of $1.825 per share.

One of the investors in the offering is our chief executive officer, who is purchasing 84,932 shares of our common stock and PIPE Warrants to purchase 84,932 shares of common stock in the concurrent private placement.

Our common stock is listed on the Nasdaq Capital Market under the symbol "INDP." On August 6, 2024, the last reported sale price of the common stock on the Nasdaq Capital Market was $1.70 per share. There is no established public trading market for the PIPE Warrants, and we do not expect a market to develop. In addition, we do not intend to list the PIPE Warrants on the Nasdaq Capital Market, any other national securities exchange or any other nationally recognized trading system.

As of the date of this prospectus supplement, the aggregate market value of our outstanding common stock held by non-affiliates is $18,766,432, which was calculated based on 7,108,497 shares of outstanding common stock that were held by non-affiliates as of July 31, 2024 and a price per share of $2.64, the closing price of our common stock on June 17, 2024. Pursuant to General Instruction I.B.6. of Form S-3, in no event will we sell securities pursuant to the registration statement (of which this prospectus supplement forms a part) with a value more than one-third of the aggregate market value of our common stock held by non-affiliates in any 12-month period, so long as the aggregate market value of our common stock held by non-affiliates is less than $75.0 million. During the prior 12-calendar-month period that ends on, and includes, the date of this prospectus, we have sold an aggregate of $375,559 of securities pursuant to General Instruction I.B.6. of Form S-3. Accordingly, we are currently eligible under General Instruction I.B.6 of Form S-3 to offer and sell shares of our common stock having an aggregate offering price of up to $5,879,918.

Investing in the common stock involves risks. See "Risk Factors" beginning on page S-3 of this prospectus supplement and on page 2 of the accompanying prospectus.

We have engaged Paulson Investment Company, LLC (the "Placement Agent"), as our exclusive placement agent in connection with the registered direct offering. The Placement Agent is not purchasing the securities offered by us in the registered direct offering and is not required to sell any specific number or dollar amount of securities, but will assist us in connection with such offering on a reasonable best efforts basis.

Per Share and PIPE Warrant Total
Offering price $ 1.825 $ 3,000,002
Placement agent fees(1) $ 0.16425 $ 256,050
Proceeds to us, before expenses (2) $ 1.66075 $ 2,588,951
(1) We have also agreed to pay the Placement Agent a fee equal to 9% of the gross proceeds raised in the offering. However, there will be no fees paid to the Placement Agent with respect to 84,932 shares sold to Mr. Meckler. See the section captioned "Plan of Distribution" in this prospectus supplement for additional information.
(2) The amount of the offering proceeds to us presented in this table does not give effect to the exercise, if any, of the PIPE Warrants being issued in the concurrent private placement.

Neither the Securities and Exchange Commission nor any state securities commission has approved or disapproved of these securities or determined if this prospectus supplement or accompanying prospectus is truthful or complete. Any representation to the contrary is a criminal offense.

Delivery of the shares of common stock offered hereby is expected to take place on or about August 8, 2024, subject to satisfaction of customary closing conditions.

Paulson Investment Company, LLC

The date of this prospectus supplement is August 7, 2024.

TABLE OF CONTENTS

PROSPECTUS SUPPLEMENT

ABOUT THIS PROSPECTUS SUPPLEMENT S-ii
PROSPECTUS SUPPLEMENT SUMMARY S-1
THE OFFERING S-2
RISK FACTORS S-3
SPECIAL NOTE REGARDING FORWARD-LOOKING STATEMENTS S-5
USE OF PROCEEDS S-6
DIVIDEND POLICY S-7
DILUTION S-8
CONCURRENT PRIVATE PLACEMENT OF PIPE WARRANTS S-9
PLAN OF DISTRIBUTION S-10
LEGAL MATTERS S-11
WHERE YOU CAN FIND MORE INFORMATION; INCORPORATION BY REFERENCE S-12

PROSPECTUS

Page
ABOUT THIS PROSPECTUS 1
RISK FACTORS 2
FORWARD-LOOKING STATEMENTS 3
OUR BUSINESS 4
USE OF PROCEEDS 6
THE SECURITIES WE MAY OFFER 7
DESCRIPTION OF SHARES OF CAPITAL STOCK 8
DESCRIPTION OF SUBSCRIPTION RIGHTS 12
DESCRIPTION OF DEBT SECURITIES 13
DESCRIPTION OF WARRANTS 25
DESCRIPTION OF UNITS 26
FORMS OF SECURITIES 27
PLAN OF DISTRIBUTION 28
LEGAL MATTERS 31
EXPERTS 31
WHERE YOU CAN FIND MORE INFORMATION 31
INCORPORATION OF CERTAIN DOCUMENTS BY REFERENCE 31
S-i

ABOUT THIS PROSPECTUS SUPPLEMENT

This document is in two parts. The first part is the prospectus supplement, including the documents incorporated by reference, which describes the specific terms of this offering. The second part, the accompanying prospectus, including the documents incorporated by reference, provides more general information. Generally, when we refer to this prospectus, we are referring to both parts of this document combined. Before you invest, you should carefully read this prospectus supplement, the accompanying prospectus, all information incorporated by reference herein and therein, as well as the additional information described under "Where You Can Find More Information; Incorporation by Reference" on page S-12 of this prospectus supplement. These documents contain information you should consider when making your investment decision. This prospectus supplement may add, update or change information contained in the accompanying prospectus. To the extent that any statement that we make in this prospectus supplement is inconsistent with statements made in the accompanying prospectus or any documents incorporated by reference, the statements made in this prospectus supplement will be deemed to modify or supersede those made in the accompanying prospectus and such documents incorporated by reference.

You should rely only on the information contained or incorporated by reference in this prospectus supplement, the accompanying prospectus and in any free writing prospectuses we may provide to you in connection with this offering. Neither we nor the Placement Agent have authorized any other person to provide you with any information that is different. If anyone provides you with different or inconsistent information, you should not rely on it. We are offering to sell, and seeking offers to buy, the securities offered hereby only in jurisdictions where offers and sales are permitted. The distribution of this prospectus supplement and the offering of the securities offered hereby in certain jurisdictions may be restricted by law. Persons outside the United States who come into possession of this prospectus supplement must inform themselves about, and observe any restrictions relating to, the offering of the securities offered hereby and the distribution of this prospectus supplement outside the United States. This prospectus supplement does not constitute, and may not be used in connection with, an offer to sell, or a solicitation of an offer to buy, any securities offered by this prospectus supplement by any person in any jurisdiction in which it is unlawful for such person to make such an offer or solicitation.

Unless otherwise indicated, information contained in this prospectus supplement, the accompanying prospectus or the documents incorporated by reference, concerning our industry and the markets in which we operate, including our general expectations and market position, market opportunity and market share, is based on information from our own management estimates and research, as well as from industry and general publications and research, surveys and studies conducted by third parties. Management estimates are derived from publicly available information, our knowledge of our industry and assumptions based on such information and knowledge, which we believe to be reasonable. In addition, assumptions and estimates of our and our industry's future performance are necessarily subject to a high degree of uncertainty and risk due to a variety of factors, including those described in "Risk Factors" in this prospectus supplement, the accompanying prospectus and in our Annual Report on Form 10-K for the year ended December 31, 2023 and Quarterly Reports on Form 10-Q for the quarter ended March 31, 2024, which are incorporated by reference into this prospectus supplement. These and other important factors could cause our future performance to differ materially from our assumptions and estimates. See "Special Note Regarding Forward-Looking Statements."

When we refer to "Indaptus," "we," "our," "us" and the "Company" in this prospectus supplement, we mean Indaptus Therapeutics, Inc. and its consolidated subsidiaries, unless otherwise specified.

This prospectus supplement also includes trademarks, tradenames and service marks that are the property of other organizations. Solely for convenience, trademarks and tradenames referred to in this prospectus supplement appear without the ® and ™ symbols, but those references are not intended to indicate, in any way, that we will not assert, to the fullest extent under applicable law, our rights or that the applicable owner will not assert its rights, to these trademarks and tradenames.

S-ii

PROSPECTUS SUPPLEMENT SUMMARY

This summary highlights selected information about us, this offering and information appearing elsewhere in this prospectus supplement, in the accompanying prospectus and in the documents we incorporate by reference. This summary is not complete and does not contain all of the information you should consider before investing in our securities. Before making an investment decision, to fully understand this offering and its consequences to you, you should carefully read this entire prospectus supplement and the accompanying prospectus, including "Risk Factors" beginning on page S-3 of this prospectus supplement and the financial statements and related notes and the other information that we incorporate by reference into this prospectus supplement.

Our Company

We are a clinical biotechnology company developing a novel and patented systemically-administered anti-cancer and anti-viral immunotherapy. We have evolved from more than a century of immunotherapy advances. Our approach is based on the hypothesis that efficient activation of both innate and adaptive immune cells and associated anti-tumor and anti-viral immune responses will require a multi-targeted package of immune system activating signals that can be administered safely intravenously. Our patented technology is composed of single strains of attenuated and killed, non-pathogenic, Gram-negative bacteria, designed to have reduced i.v. toxicity, but largely uncompromised ability to prime or activate many of the cellular components of innate and adaptive immunity. This approach has led to broad anti-tumor and anti-viral activity in preclinical models, including durable anti-tumor response synergy observed with each of four different classes of existing agents, including NSAIDs, checkpoint therapy, targeted antibody therapy and low-dose chemotherapy. Tumor eradication by our technology was associated with induction of both innate and adaptive immunological memory and, importantly, did not require provision of or targeting a tumor antigen in preclinical models. We have carried out successful current Good Manufacturing Practice (cGMP) manufacturing of our lead clinical candidate, Decoy20.

Corporate Information

Our principal executive offices are located at 3 Columbus Circle, 15th Floor, New York, NY 10019 and our telephone number is (646) 427-2727. Our website address is http://www.indaptusrx.com. The information contained on, or that can be accessed through, our website is neither a part of nor incorporated into this prospectus. We have included our website address in this prospectus solely as an inactive textual reference.

S-1

THE OFFERING

Common stock offered by us 1,643,837 shares.
Common stock to be outstandingimmediately after this offering 10,182,720 shares (assuming no exercise of the PIPE Warrants to be issued in the concurrent private placement).
Concurrent private placement of PIPE Warrants In a concurrent private placement, we are selling to the institutional and accredited investors PIPE Warrants to purchase up to an aggregate of 1,643,837 shares of our common stock. Each PIPE Warrant will be exercisable for one share of our common stock at an exercise price of $1.70 per share and will have a term of five years from the date of issuance. The PIPE Warrants and PIPE Warrant Shares are being offered pursuant to the exemptions provided in Section 4(a)(2) under the Securities Act, and Rule 506(b) promulgated thereunder, and they are not being offered pursuant to this prospectus supplement and the accompanying prospectus. Please see "Concurrent Private Placement of PIPE Warrants" on page S-9.
Use of proceeds We estimate the net proceeds from this offering will be approximately $2.5 million, after deducting placement agent fees and estimated offering expenses payable by us.
We intend to use the net proceeds of this offering to fund our research and development activities and for working capital and general corporate purposes. Please see "Use of Proceeds" on page S-6.
Risk factors See "Risk Factors" beginning on page S-3 of this prospectus supplement and in the documents incorporated by reference into this prospectus supplement for a discussion of factors that you should read and consider before investing in our securities.
Listing Our common stock is listed on The Nasdaq Capital Market under the symbol "INDP."
Transfer agent VStock Transfer, LLC

The number of shares of our common stock to be outstanding immediately after this offering is based on 8,538,883 shares of our common stock outstanding as of March 31, 2024 and excludes:

2,395,947 shares of common stock issuable upon exercise of outstanding options under our Indaptus 2021 Stock Incentive Plan, or the 2021 Plan, at a weighted exercise price of $9.50;
95,483 shares of common stock reserved for potential future issuance pursuant to the 2021 Plan;
3,090,787 shares of common stock issuable upon the exercise of outstanding warrants at a weighted exercise price of $12.50 per share; and
3,857,550 shares of common stock reserved for issuance pursuant to a committed equity facility with Lincoln Park Capital Fund, LLC, or the Committed Equity Facility.

Unless otherwise indicated, this prospectus supplement reflects and assumes:

no exercise of the outstanding options described above; and
no exercise of the outstanding warrants described above.
S-2

RISK FACTORS

Investing in our securities involves a high degree of risk. Before investing in our securities, you should consider carefully the risks described below, together with the other information contained in this prospectus supplement, the accompanying prospectus or incorporated by reference herein or therein, including the risks and uncertainties discussed under "Risk Factors" in our Annual Report on Form 10-K for the year ended December 31, 2023 and Quarterly Report on Form 10-Q for the quarter ended March 31, 2024, which are incorporated by reference into this prospectus supplement. If any of the risks incorporated by reference or set forth below occur, our business, financial condition, results of operations and future growth prospects could be materially and adversely affected. In these circumstances, the market price of our securities could decline, and you may lose all or part of your investment.

Risks Related to this Offering

Purchasers of common stock and accompanying PIPE Warrants in this offering will experience immediate and substantial dilution in the book value of their investment. You may experience further dilution upon exercise of options and warrants.

The offering price per share of common stock and accompanying PIPE Warrants in this offering is substantially higher than the net tangible book value per share of our common stock before giving effect to this offering. Accordingly, if you purchase common stock and accompanying PIPE Warrants in this offering, you will incur immediate substantial dilution of approximately $0.6588 per share, representing the difference between the offering price per share of common stock and accompanying PIPE Warrants and our as adjusted net tangible book value as of March 31, 2024. For a further description of the dilution that you will experience immediately after this offering, see the section in this prospectus supplement entitled "Dilution."

Future sales and issuances of our common stock or rights to purchase common stock, including pursuant to our equity incentive plans, could result in additional dilution of the percentage ownership of our stockholders and could cause our stock price to fall.

Additional capital will be needed in the future to continue our planned operations. To the extent we issue additional equity securities to raise capital or pursuant to our equity incentive plans or other contractual obligations, our stockholders may experience substantial dilution. We may sell common stock, convertible securities or other equity securities in one or more transactions at prices and in a manner we determine from time to time. If we sell or issue common stock, convertible securities or other equity securities in more than one transaction, investors may be materially diluted by subsequent sales. These sales may also result in material dilution to our existing stockholders, and new investors could gain rights superior to our existing stockholders.

In addition, sales of a substantial number of shares of our outstanding common stock in the public market could occur at any time. These sales, or the perception in the market that the holders of a large number of shares of common stock intend to sell shares, could reduce the market price of our common stock. Significant portions of these shares are held by a relatively small number of stockholders. Sales by our stockholders of a substantial number of shares, or the expectation that such sales may occur, could significantly reduce the market price of our common stock.

S-3

We have broad discretion to determine how to use the funds raised in this offering, and may use them in ways that may not enhance our operating results or the price of our common stock.

Our management will have broad discretion over the use of proceeds from this offering, and we could spend the proceeds from this offering in ways our stockholders may not agree with or that do not yield a favorable return, if at all. We intend to use the net proceeds to fund our research and development activities and for working capital and general corporate purposes. However, our use of these proceeds may differ substantially from our current plans. If we do not invest or apply the proceeds of this offering in ways that improve our operating results, we may fail to achieve expected financial results, which could cause our stock price to decline.

We have identified conditions and events that raise substantial doubt regarding our ability to continue as a going concern.

We have incurred net losses and utilized cash in operations since inception. In addition, as of March 31, 2024, we had approximately $9.7 million in cash and cash equivalents, and during the three months ended March 31, 2024, we used approximately $3.9 million of cash in operations and expect to continue to incur significant cash outflows and incur future additional losses to execute our operating plan. While we intend to finance our cash needs principally through collaborations, strategic alliances, or license agreements with third parties and/or debt or equity financings, we cannot provide any assurance that new financing will be available to us on commercially acceptable terms or in the amounts required, if at all. Due to the uncertainty in securing additional funding, and the insufficient amount of cash and cash equivalents as of March 31, 2024, we have concluded that substantial doubt exists about our ability to continue as a going concern within one year after the date of the filing of our Quarterly Report on Form 10-Q for the quarter ended March 31, 2024, which was May 8, 2024. While the closing of this offering will improve our cash position, the net proceeds from this transaction may not be sufficient to overcome the previously disclosed substantial doubt regarding our ability to continue as a going concern. If we are unsuccessful in securing sufficient financing, we may need to delay, reduce, or eliminate our research and development programs, which could adversely affect our business prospects, or cease operations.

Our future operations are dependent upon the successful entry into collaborations, strategic alliances, or license agreements with third parties and/or on the identification and successful completion of equity or debt financing and the achievement of profitable operations at an indeterminate time in the future. There can be no assurances that we will be successful in completing these collaborations or alliances, equity or debt financing or in achieving profitability. As such, there can be no assurance that we will be able to continue as a going concern.

Substantial doubt about our ability to continue as a going concern may materially and adversely affect the price per share of our common stock, and it may be more difficult for us to obtain financing. If potential collaborators decline to do business with us or potential investors decline to participate in any future financings due to such concerns, our ability to increase our cash position may be limited. The perception that we may not be able to continue as a going concern may cause others to choose not to deal with us due to concerns about our ability to meet our contractual obligations. If we are unable to continue as a going concern, you could lose all or part of your investment in our company.

A substantial number of shares of our common stock will be sold in this offering, which could cause the price of our common stock to decline.

In this offering, we will sell 1,643,837 shares of our common stock, which represented approximately 16% of our outstanding shares of common stock as of June 30, 2024 after giving effect to this offering. In addition, in a concurrent private placement, we are selling PIPE Warrants to purchase up to 1,643,837 shares of common stock at an exercise price of $1.70 per share. This sale could adversely affect the price of our common stock on The Nasdaq Capital Market. We cannot predict the effect, if any, that market sales of the shares of common stock issued in this offering or issued upon exercise of the warrants issued in this offering will have on the market price of our common stock. In addition, a decline in the price of our common stock might impede our ability to raise capital through the issuance of additional shares of our common stock or other equity securities, and may cause you to lose part or all of your investment in our common stock.

S-4

SPECIAL NOTE REGARDING FORWARD-LOOKING STATEMENTS

The information in this prospectus supplement, the accompanying prospectus and the documents incorporated by reference herein and therein and any free writing prospectus that we have authorized for use in connection with this offering contain forward-looking statements and information within the meaning of Section 27A of the Securities Act and Section 21E of the Securities Exchange Act of 1934, as amended, or the Exchange Act, which are subject to the "safe harbor" created by those sections. These forward-looking statements include, but are not limited to, statements regarding our product candidates' development, including the timing and design of the Phase 1 clinical trial of Decoy20; our expectations regarding the recommended Phase 2 dose for subsequent multi-dosing and combination studies and related timing; the anticipated effects of our product candidates; our plans to develop and commercialize our product candidates; the market potential and treatment potential of our product candidates, including Decoy20; our commercialization, marketing and manufacturing capabilities and strategy; our expectations about the willingness of healthcare professionals to use our product candidates; our general business strategy and the plans and objectives of management for future operations; our research and development activities and costs; our future results of operations and condition; the sufficiency of our cash and cash equivalents to fund our ongoing activities and our ability to continue as a going concern; the impact of current macroeconomic conditions on our operations, ability to access capital, and liquidity. The words "anticipates", "believes", "estimates", "expects", "intends", "targets", "may", "plans", "projects", "potential", "will", "would", "could" and similar expressions are intended to identify forward-looking statements, although not all forward-looking statements contain these identifying words. All such forward-looking statements involve significant risks and uncertainties, including, but not limited to, statements regarding:

our plans to develop and potentially commercialize our technology;
the timing and cost of our planned investigational new drug application and any clinical trials;
the completion and receipt of favorable results in any clinical trials;
our ability to obtain and maintain regulatory approval of any product candidate;
our ability to protect and maintain our intellectual property and licensing arrangements;
our ability to develop, manufacture and commercialize our product candidates;
the risk of product liability claims, the availability of reimbursement, the influence of extensive and costly government regulation;
our estimates regarding future revenue, expenses capital requirements and the need for additional financing;
our ability to continue as a going concern; and
our intended use of proceeds from this offering.

As more fully described under the heading "Risk Factors" and elsewhere in this prospectus supplement and under "Risk Factors" in our Annual Report on Form 10-K for the year ended December 31, 2023 and Quarterly Report on Form 10-Q for the quarter ended March 31, 2024, which are incorporated by reference into this prospectus supplement, many important factors affect our ability to achieve our stated objectives and to develop and commercialize any product candidates. We may not actually achieve the plans, intentions or expectations disclosed in our forward-looking statements and you should not place undue reliance on our forward-looking statements. These forward-looking statements involve risks and uncertainties that could cause our actual results to differ materially from those in the forward-looking statements, including, without limitation, the risks and uncertainties set forth in our filings with the SEC. You should read this prospectus supplement, the accompanying prospectus and the documents incorporated by reference herein and therein and any free writing prospectuses that we have authorized for use in this offering with the understanding that our actual results or events could differ materially from the plans, intentions and expectations disclosed in the forward-looking statements that we make. The forward-looking statements are applicable only as of the date on which they are made, and we do not assume any obligation to update any forward-looking statements, whether as a result of new information, future events or otherwise, except as required by law.

S-5

USE OF PROCEEDS

We estimate that the net proceeds from this offering and the concurrent private placement, after deducting placement agent fees and estimated offering expenses payable by us, will be approximately $2.5 million. This estimate excludes the proceeds, if any, from the PIPE Warrants sold in the concurrent private placement. We cannot predict when or if any such warrants will be exercised. It is possible that the warrants may expire and may never be exercised.

We intend to use the net proceeds of this offering to fund our research and development activities and for working capital and general corporate purposes.

Based on the planned use of proceeds, we believe that the net proceeds from this offering and the concurrent private placement and our existing cash and cash equivalents will be sufficient to enable us to fund our operating expenses and capital expenditure requirements into the first quarter of 2025. We have based this estimate on assumptions that may prove to be incorrect, and we could utilize our available capital resources sooner than we currently expect. The amounts and timing of our actual expenditures will depend on numerous factors, including the factors described under "Risk Factors" in this prospectus supplement, the accompanying prospectus and the documents incorporated by reference herein and therein, as well as the amount of cash used in our operations. We may find it necessary or advisable to use the net proceeds for other purposes, and we will have broad discretion in the application of the net proceeds. While the closing of this offering will improve our cash position, the net proceeds from this transaction may not be sufficient to overcome the previously disclosed substantial doubt regarding our ability to continue as a going concern.

Pending the uses described above, we plan to invest the net proceeds from this offering in short-term, interest-bearing securities, investment grade securities, certificates of deposit or direct or guaranteed obligations of the U.S. government. In addition, while we have not entered into any agreements, commitments or understandings relating to any significant transaction as of the date of this prospectus supplement, we may use a portion of the net proceeds to pursue acquisitions, joint ventures and other strategic transactions.

S-6

DIVIDEND POLICY

We have never declared or paid cash dividends on our capital stock. We currently intend to retain our future earnings, if any, for use in our business and therefore do not anticipate paying cash dividends in the foreseeable future. Payment of future dividends, if any, will be at the discretion of our board of directors after taking into account various factors, including our financial condition, operating results, current and anticipated cash needs and plans for expansion.

S-7

DILUTION

If you invest in this offering, your ownership interest will be immediately diluted to the extent of the difference between the offering price per share of common stock and accompanying PIPE Warrant and the as adjusted net tangible book value per share of our common stock after this offering.

As of March 31, 2024, we had a net tangible book value of approximately $9.4 million, or $1.0946 per share of common stock. Our net tangible book value per share represents total tangible assets less total liabilities, divided by the number of shares of common stock outstanding at March 31, 2024.

After giving effect to the issuance and sale by us of 1,643,836 shares of common stock and PIPE Warrants to purchase 1,643,836 shares of common stock at an offering price of $1.825 per share and accompanying PIPE Warrant in this offering and after deducting placement agent fees and estimated offering expenses payable by us, and assuming no exercise of the PIPE Warrants, our as adjusted net tangible book value as of March 31, 2024 would have been approximately $11.9 million, or approximately $1.1662 per share. This amount represents an immediate increase in net tangible book value of $0.0716 per share to our existing stockholders and an immediate dilution in as adjusted net tangible book value of approximately $0.6588 per share to new investors purchasing securities in this offering.

Dilution per share to new investors is determined by subtracting as adjusted net tangible book value per share after this offering from the offering price per share of common stock and accompanying PIPE Warrant paid by new investors. The following table illustrates this dilution on a per share basis:

Offering price per share of common stock and accompanying PIPE Warrant $ 1.8250
Net tangible book value per share as of March 31, 2024 $ 1.0946
Increase in net tangible book value per share attributable to this offering 0.0716
As adjusted net tangible book value per share after this offering 1.1662
Dilution per share to new investors participating in this offering $ 0.6588

The above discussion and table are based on 8,538,883 shares of our common stock outstanding as of March 31, 2024 and excludes:

2,395,947 shares of common stock issuable upon exercise of outstanding options under the 2021 Plan at a weighted exercise price of $9.50;
95,483 shares of common stock reserved for potential future issuance pursuant to the 2021 Plan;
3,090,787 shares of common stock issuable upon the exercise of warrants outstanding at a weighted exercise price of $12.50 per share; and
3,857,550 shares of common stock reserved for issuance pursuant to the Committed Equity Facility.

To the extent any of these outstanding options or warrants are exercised at a price less than the offering price, there may be further dilution to purchasers of our securities in this offering.

S-8

CONCURRENT PRIVATE PLACEMENT OF PIPE WARRANTS

In the concurrent private placement, we will issue to the investors in this offering, PIPE Warrants to purchase up to an aggregate of 1,643,837 shares of common stock at an exercise price equal to $1.70 per share (subject to standard adjustments for stock splits, stock dividend, rights offerings and pro rata distributions). The PIPE Warrant is being sold together with the shares of common stock being sold in this offering, and we will receive additional proceeds from the PIPE Warrant to the extent such PIPE Warrant is exercised for cash.

The PIPE Warrant and the PIPE Warrant Shares issuable upon the exercise of such PIPE Warrant are not being registered under the Securities Act, are not being offered pursuant to this prospectus supplement and the accompanying prospectus and are being offered pursuant to the exemption provided in Section 4(a)(2) under the Securities Act and/or Rule 506(b) promulgated thereunder. Accordingly, the purchaser may only sell common stock issued upon exercise of the PIPE Warrant pursuant to an effective registration statement under the Securities Act covering the resale of those shares, an exemption under Rule 144 under the Securities Act or another applicable exemption under the Securities Act.

We have agreed to file a registration statement within sixty days of the date of the Purchase Agreement to register the PIPE Warrant Shares for resale. We have also agreed to use commercially reasonable efforts to cause such registration statement to become effective within ninety days following the closing date of this offering and to use commercially reasonable efforts to keep such registration statement effective at all times until the date that no purchaser owns any PIPE Warrants or PIPE Warrant Shares issuable upon exercise thereof.

The summary below is not complete and is subject to, and qualified in its entirety by, the provisions of Purchase Agreement and the PIPE Warrants, which will be filed with the SEC as an exhibit to a Current Report on Form 8-K in connection with the concurrent private placement and incorporated by reference into the registration statement of which this prospectus supplement and the accompanying prospectus form a part. Prospective investors should carefully review the terms and provisions of the form of PIPE Warrant for a complete description of the terms and conditions of the PIPE Warrant.

Duration and Exercise Price

The PIPE Warrant has an exercise price of $1.70 per share and will be immediately exercisable upon issuance. The PIPE Warrant will expire five years following the issuance of the PIPE Warrant. The PIPE Warrant contains standard adjustments to the exercise price including for stock splits, stock dividend, rights offerings and pro rata distributions.

Exercisability

The PIPE Warrant will be immediately exercisable, at the option of each holder and until the expiration date, in whole or in part, by delivering to us a duly executed exercise notice accompanied by payment in full for the number of purchased upon such exercise (except in the case of a cashless exercise as discussed below).

Exercise Limitation

A holder (together with its affiliates) may not exercise any portion of the PIPE Warrant to the extent that the holder would beneficially own more than 4.99% or 9.99%, depending on the individual investor, of the outstanding common stock immediately after exercise (the "Beneficial Ownership Limitation"), except that upon at least 61 days' prior notice from the holder to us, the holder may increase the Beneficial Ownership Limitation, provided that the Beneficial Ownership Limitation in no event exceeds 19.99%. No fractional shares of common stock will be issued in connection with the exercise of a PIPE Warrant. In lieu of fractional shares, we will pay the holder either an amount in cash equal to the fractional amount multiplied by the exercise price or round such fractional share to a whole share.

Cashless Exercise

In lieu of making the cash payment otherwise contemplated to be made to us upon such exercise in payment of the aggregate exercise price, the holder may, in the event the shares underlying the PIPE Warrant, or the PIPE Warrant Shares, are not registered under the Securities Act, elect instead to receive upon such exercise (either in whole or in part) the net number of shares of common stock determined according to a formula set forth in the PIPE Warrant.

Transferability

Subject to applicable laws, a PIPE Warrant may be transferred at the option of the holder upon surrender of the PIPE Warrant to us together with the appropriate instruments of transfer.

Exchange Listing

We do not intend to list the PIPE Warrants on any securities exchange or nationally recognized trading system.

Rights as a Stockholder

Except as otherwise provided in the PIPE Warrant or by virtue of such holder's ownership of common stock, the holders of the PIPE Warrant do not have the rights or privileges of holders of our common stock, including any voting rights, until they exercise the PIPE Warrant.

S-9

PLAN OF DISTRIBUTION

Subject to the terms and conditions of a placement agency agreement, Paulson Investment Company, LLC, which we refer to as the placement agent, has agreed to act as our exclusive placement agent in connection with this offering of our securities pursuant to this prospectus supplement and the accompanying prospectus. The placement agent is not purchasing or selling any securities offered by this prospectus supplement and the accompanying prospectus. We have entered into purchase agreements directly with investors in connection with this offering and we will only sell securities offered hereby to investors which have entered into purchase agreements. The public offering price of the securities was determined based upon arm's-length negotiations between the purchasers and us.

Commissions and Expenses

We have agreed to pay the placement agent an aggregate cash placement fee equal to nine percent (9.0%) of the gross proceeds in this offering. There will be no fees paid to the Placement Agent with respect to 84,932 shares sold to our Chief Executive Officer.

The following table provides information regarding the amount of the placement agent fees to be paid to the placement agent by us, before expenses assuming the purchase of all of the securities offered hereby:

Per share and
PIPE Warrant
Total
Offering price $ 1.825 $ 3,000,002
Placement Agent fees $ 0.16425 $ 256,050

Because there is no minimum offering amount required as a condition to closing in this offering, the actual total offering commissions, if any, are not presently determinable and may be substantially less than the maximum amount set forth above. We have also agreed to pay the placement agent a non-accountable sum of $50,000 in connection with this offering.

Our obligation to issue and sell securities to the purchasers is subject to the conditions set forth in the purchase agreements, which may be waived by us at our discretion. A purchaser's obligation to purchase securities is subject to the conditions set forth in such purchaser's purchase agreement, which may also be waived at such purchaser's discretion.

We currently anticipate that the sale of the securities will be completed on or about August 8, 2024. We estimate the total offering expenses of this offering that will be payable by us, excluding the placement agent's fees, will be approximately $200,000, which includes legal and printing costs, various other fees and reimbursement of the placements agent's expenses.

Indemnification

We have agreed to indemnify the placement agent against certain liabilities, including liabilities under the Securities Act of 1933, as amended, or the Securities Act, and the Exchange Act. We have also agreed to contribute to payments the placement agent may be required to make in respect of such liabilities.

The placement agent may be deemed to be an underwriter within the meaning of Section 2(a)(11) of the Securities Act, and any commissions received by it and any profit realized on the sale of our securities offered hereby by it while acting as principal might be deemed to be underwriting discounts or commissions under the Securities Act. As an underwriter, the placement agent would be required to comply with the requirements of the Securities Act and the Exchange Act, including, without limitation, Rule 10b-5 and Regulation M under the Exchange Act. These rules and regulations may limit the timing of purchases and sales of our securities by the placement agent acting as principal. Under these rules and regulations, the placement agent may not (i) engage in any stabilization activity in connection with our securities or (ii) bid for or purchase any of our securities or attempt to induce any person to purchase any of our securities, other than as permitted under the Exchange Act, until it has completed its participation in the distribution.

The foregoing does not purport to be a complete statement of the terms and conditions of the placement agent agreement and purchase agreements. A copy of the placement agent agreement and the form of purchase agreement with the investors will be included as exhibits to our Current Report on Form 8-K that will be filed with the SEC and incorporated by reference into the Registration Statement of which this prospectus supplement forms a part. See "Where You Can Find More Information."

Other

From time to time, the placement agent and its affiliates have provided, or may in the future provide, various investment banking, financial advisory and other services to us and our affiliates for which services they have received, or may in the future receive, customary fees. There are no present arrangements for such future services. In the course of their businesses, the placement agent and its affiliates may actively trade our securities or loans for their own account or for the accounts of customers, and, accordingly, the placement agent and its affiliates may at any time hold long or short positions in such securities or loans.

Our common stock is listed on The Nasdaq Capital Market under the symbol "INDP". the Common Warrants on The Nasdaq Capital Market or any other securities exchange or trading market.

S-10

LEGAL MATTERS

The validity of the securities offered hereby will be passed upon for us by Latham & Watkins LLP. Lowenstein Sandler LLP is counsel to the Placement Agent in connection with this offering.

EXPERTS

Our consolidated financial statements as of December 31, 2023 and 2022, and for each of the years then ended, have been incorporated by reference herein in reliance upon the report of Haskell & White LLP, independent registered public accounting firm, and upon the authority of said firm as experts in accounting and auditing.

S-11

WHERE YOU CAN FIND MORE INFORMATION; INCORPORATION BY REFERENCE

Available Information

We file reports, proxy statements and other information with the SEC. The SEC maintains a web site that contains reports, proxy and information statements and other information about issuers, such as us, who file electronically with the SEC. The address of that website is www.sec.gov.

Our web site address is www.indaptusrx.com. The information on our web site, however, is not, and should not be deemed to be, a part of this prospectus supplement.

This prospectus supplement and the accompanying prospectus are part of a registration statement that we filed with the SEC and do not contain all of the information in the registration statement. The full registration statement may be obtained from the SEC or us, as provided below. Other documents establishing the terms of the offered securities are or may be filed as exhibits to the registration statement. Statements in this prospectus supplement about these documents are summaries and each statement is qualified in all respects by reference to the document to which it refers. You should refer to the actual documents for a more complete description of the relevant matters. You may inspect a copy of the registration statement through the SEC's website, as provided above.

Incorporation by Reference

The SEC's rules allow us to "incorporate by reference" information into this prospectus supplement and the accompanying prospectus, which means that we can disclose important information to you by referring you to another document filed separately with the SEC. The information incorporated by reference is deemed to be part of this prospectus supplement and the accompanying prospectus, and subsequent information that we file with the SEC will automatically update and supersede that information. Any statement contained in a previously filed document incorporated by reference will be deemed to be modified or superseded for purposes of this prospectus supplement and the accompanying prospectus to the extent that a statement contained in this prospectus supplement or the accompanying prospectus modifies or replaces that statement.

We incorporate by reference the following information or documents that we have filed with the SEC:

Our Annual Report on Form 10-K for the year ended December 31, 2023, filed with the SEC on March 13, 2024.
Our Quarterly Report on Form 10-Q for the quarter ended March 31, 2023, filed with the SEC on May 8, 2024.
Our Current Reports on Form 8-K filed with the SEC on January 23, 2024, March 4, 2024, March 25, 2024, May 22, 2024 and June 7, 2024.
Our annual Proxy Statement on Schedule 14A relating to our annual meeting of stockholders, filed on April 26, 2024 (with respect to those portions incorporated by reference into our Annual Report on Form 10-K for the year ended December 31, 2023).
The description of our common stock contained in our Registration Statement on Form 8-A, filed with the SEC on July 23, 2021, and any amendment or report filed with the SEC for the purpose of updating the description.

We incorporate by reference into this prospectus supplement and accompanying prospectus all reports and other documents we subsequently file with the SEC pursuant to Sections 13(a), 13(c), 14 or 15(d) of the Securities Exchange Act of 1934, as amended, between the date of this prospectus supplement and the termination of the offering of the securities described in this prospectus supplement. We are not, however, incorporating by reference any documents or portions thereof, whether specifically listed above or filed in the future, that are not deemed "filed" with the SEC, including any information furnished pursuant to Items 2.02 or 7.01 of Form 8-K or related exhibits furnished pursuant to Item 9.01 of Form 8-K. The reports and documents specifically listed above or filed in the future (excluding any information furnished to, rather than filed with, the SEC) are deemed to be part of this prospectus supplement and accompanying prospectus from the date of the filing of such reports and documents.

You may request a free copy of any of the documents incorporated by reference in this prospectus supplement and the accompanying prospectus (other than exhibits, unless they are specifically incorporated by reference in the documents) by writing or telephoning us at the following address:

Indaptus Therapeutics, Inc.
3 Columbus Circle, 15th Floor
New York, NY 10019
(646) 427-2727

Exhibits to the filings will not be sent, however, unless those exhibits have specifically been incorporated by reference in this prospectus supplement and the accompanying prospectus.

S-12

PROSPECTUS

$200,000,000

Common Stock

Preferred Stock

Subscription Rights

Debt Securities

Warrants

Units

INDAPTUS THERAPEUTICS, INC.

We may offer, issue and sell from time to time up to $200,000,000, of our common stock, preferred stock, subscription rights, debt securities, warrants and a combination of such securities, separately or as units, in one or more offerings. This prospectus provides a general description of offerings of these securities that we may undertake.

We refer to the shares of common stock, preferred stock, subscription rights, debt securities, warrants and units collectively as "securities" in this prospectus.

Each time we sell securities pursuant to this prospectus, we will provide in a supplement to this prospectus the price and any other material terms of any such offering. Any prospectus supplement may also add, update or change information contained in this prospectus. You should read this prospectus and any applicable prospectus supplement, as well as the documents incorporated by reference or deemed incorporated by reference into this prospectus, carefully before you invest in any securities. This prospectus may not be used to offer or sell securities unless accompanied by a prospectus supplement.

We may, from time to time, offer to sell the securities, through public or private transactions, directly or through underwriters, agents or dealers, on or off the Nasdaq Capital Market, at prevailing market prices or at privately negotiated prices. If any underwriters, agents or dealers are involved in the sale of any of these securities, the applicable prospectus supplement will set forth the names of the underwriter, agent or dealer and any applicable fees, commissions or discounts.

Our shares of common stock are traded on the Nasdaq Capital Market under the symbol "INDP." The last reported sale price of our shares of common stock, as reported on the Nasdaq Capital Market on August 31, 2022 was $2.52.

The aggregate market value of our outstanding common stock held by non-affiliates pursuant to General Instruction I.B.6 of Form S-3 was $19,171,306, which was calculated based on 8,258,597 shares of common stock outstanding, as of August 31, 2022, of which 5,757,149 shares were held by non-affiliates, and a price per share of $3.33 which was the closing sale price of our common stock on the Nasdaq Capital Market on August 5, 2022. We have not offered any securities pursuant to General Instruction I.B.6 of Form S-3 during the 12 calendar months prior to and including the date of this prospectus.

Investing in our securities involves risks. See the section entitled "Risk Factors" included in or incorporated by reference into the accompanying prospectus supplement beginning on page 2 and in the documents we incorporate by reference in this prospectus.

Neither the Securities and Exchange Commission nor any state securities commission has approved or disapproved of these securities or passed upon the adequacy or accuracy of this prospectus. Any representation to the contrary is a criminal offense.

The date of this prospectus is September 9, 2022

TABLE OF CONTENTS

Page
ABOUT THIS PROSPECTUS 1
RISK FACTORS 2
FORWARD-LOOKING STATEMENTS 3
OUR BUSINESS 4
USE OF PROCEEDS 6
THE SECURITIES WE MAY OFFER 7
DESCRIPTION OF SHARES OF CAPITAL STOCK 8
DESCRIPTION OF SUBSCRIPTION RIGHTS 12
DESCRIPTION OF DEBT SECURITIES 13
DESCRIPTION OF WARRANTS 25
DESCRIPTION OF UNITS 26
FORMS OF SECURITIES 27
PLAN OF DISTRIBUTION 28
LEGAL MATTERS 31
EXPERTS 31
WHERE YOU CAN FIND MORE INFORMATION 31
INCORPORATION OF CERTAIN DOCUMENTS BY REFERENCE 31
i

ABOUT THIS PROSPECTUS

This prospectus is part of a registration statement that we filed with the Securities and Exchange Commission, or SEC, utilizing a "shelf" registration process. Under this shelf registration process, we may offer and sell separately or together in any combination the securities described in this prospectus in one or more offerings up to a total price to the public of $200,000,000. The offer and sale of securities under this prospectus may be made from time to time, in one or more offerings, in any manner described under the section in this prospectus entitled "Plan of Distribution." This prospectus does not contain all of the information set forth in the registration statement, certain parts of which are omitted in accordance with the rules and regulations of the SEC. Accordingly, you should refer to the registration statement and its exhibits for further information about us and our securities. Copies of the registration statement and its exhibits are on file with the SEC. Statements contained in this prospectus concerning the documents we have filed with the SEC are not intended to be comprehensive, and in each instance we refer you to a copy of the actual document filed as an exhibit to the registration statement or otherwise filed with the SEC.

This prospectus provides you with a general description of the securities we may offer. Each time we sell securities we will provide this prospectus and a prospectus supplement that will contain specific information about the terms of that offering. The prospectus supplement may also add, update or change information contained in this prospectus, and may also contain information about any material federal income tax considerations relating to the securities covered by the prospectus supplement. You should carefully read both this prospectus and any prospectus supplement together with additional information under the headings "Where You Can Find More Information" and "Incorporation of Certain Documents by Reference."

The prospectus supplement to be attached to the front of this prospectus may describe, as applicable: the terms of the securities offered; the public offering price; the price paid for the securities; net proceeds; and the other specific terms related to the offering of the securities.

We have not authorized anyone to provide you with information different from that contained or incorporated by reference in this prospectus or any accompanying prospectus supplement or any "free writing prospectus." We are offering to sell, and seeking offers to buy, securities only in jurisdictions where offers and sales are permitted. The information contained in this prospectus and in any accompanying prospectus supplement is accurate only as of the dates of their covers, regardless of the time of delivery of this prospectus or any prospectus supplement or of any sale of our securities. Our business, financial condition, results of operations, and prospects may have changed since those dates. You should rely only on the information contained or incorporated by reference in this prospectus or any accompanying prospectus supplement. To the extent there is a conflict between the information contained in this prospectus and the prospectus supplement, you should rely on the information in the prospectus supplement, provided that if any statement in one of these documents is inconsistent with a statement in another document having a later date - for example, a document incorporated by reference into this prospectus or any prospectus supplement - the statement in the document having the later date modifies or supersedes the earlier statement.

This prospectus incorporates by reference market data and certain industry data and forecasts that were obtained from market research databases, consultant surveys commissioned by us, publicly available information, reports of governmental agencies and industry publications and surveys. Industry surveys, publications, consultant surveys commissioned by us and forecasts generally state that the information contained therein has been obtained from sources believed to be reliable. We have relied on certain data from third-party sources, including internal surveys, industry forecasts and market research, which we believe to be reliable based on our management's knowledge of the industry. Statements as to our market position are based on the most currently available data. While we are not aware of any misstatements regarding the industry data presented in this prospectus, our estimates involve risks and uncertainties and are subject to change based on various factors, including those discussed or referred to under the heading "Risk Factors" in this prospectus, and under similar headings in the other documents that are incorporated herein by reference.

Certain figures included in this prospectus have been subject to rounding adjustments. Accordingly, figures shown as totals in certain tables may not be an arithmetic aggregation of the figures that precede them.

All references to "we," "us," "our," "Indaptus Therapeutics", "Indaptus", "the Company" and "our company", in this prospectus are to Indaptus Therapeutics, Inc. (formerly Intec Parent, Inc.) and, where appropriate, its consolidated subsidiaries Intec Pharma Ltd. and Decoy Biosystems, Inc. References to "Intec Parent" refer to Intec Parent, Inc., the successor of Intec Pharma Ltd. following the Domestication Merger, references to "Intec Israel" refer to Intec Pharma Ltd., the predecessor of Indaptus prior to the Domestication Merger, and references to "Decoy" refer to Decoy Biosystems, Inc., the entity acquired by Indaptus in connection with the Merger described elsewhere in this prospectus.

1

RISK FACTORS

An investment in our securities involves a high degree of risk. The prospectus supplement applicable to each offering of our securities will contain a discussion of the risks applicable to an investment in our securities. Before deciding whether to invest in our securities, you should carefully consider the specific factors discussed under the heading "Risk Factors" in the applicable prospectus supplement, together with all of the other information contained or incorporated by reference in the prospectus supplement or appearing or incorporated by reference in this prospectus. You should also consider the risks, uncertainties and assumptions discussed under Item 1A, "Risk Factors," in our Annual Report on Form 10-K for the fiscal year ended December 31, 2021, and any subsequent Quarterly Report on Form 10-Q or Current Report on Form 8-K which are incorporated herein by reference, as updated or superseded by the risks and uncertainties described under similar headings in the other documents that are filed after the date hereof and incorporated by reference into this prospectus and any prospectus supplement related to a particular offering. The risks and uncertainties we have described are not the only ones we face. Additional risks and uncertainties not presently known to us or that we currently deem immaterial may also affect our operations. Past financial performance may not be a reliable indicator of future performance, and historical trends should not be used to anticipate results or trends in future periods. If any of these risks actually occurs, our business, business prospects, financial condition or results of operations could be seriously harmed. This could cause the trading price of our common stock to decline, resulting in a loss of all or part of your investment. Please also read carefully the section below entitled "Forward-Looking Statements."

2

FORWARD-LOOKING STATEMENTS

This prospectus, including the information incorporated by reference into this prospectus, contains, and any prospectus supplement may contain statements that are forward-looking statements about our expectations, beliefs or intentions regarding, among other things, our product development efforts, business, financial condition, results of operations, strategies, plans and prospects. In addition, from time to time, we or our representatives have made or may make forward-looking statements, orally or in writing. Forward-looking statements can be identified by the use of forward-looking words such as "believe," "expect," "intend," "plan," "may," "should," "anticipate," "could," "might," "seek," "target," "will," "project," "forecast," "continue" or their negatives or variations of these words or other comparable words or by the fact that these statements do not relate strictly to historical matters. These forward-looking statements may be included in, among other things, various filings made by us with the SEC, press releases or oral statements made by or with the approval of one of our authorized executive officers. Forward-looking statements relate to anticipated or expected events, activities, trends or results as of the date they are made. Because forward-looking statements relate to matters that have not yet occurred, these statements are inherently subject to risks and uncertainties that could cause our actual results to differ materially from any future results expressed or implied by the forward-looking statements. Many factors could cause our actual activities or results to differ materially from the activities and results anticipated in forward-looking statements, including, but not limited to:

our plans to develop and potentially commercialize our technology;
the timing and cost of our planned investigational new drug application and any clinical trials;
the completion and receipt of favorable results in any clinical trials;
our ability to obtain and maintain regulatory approval of any product candidate;
our ability to protect and maintain our intellectual property and licensing arrangements;
our ability to develop, manufacture and commercialize our product candidates;
the risk of product liability claims, the availability of reimbursement, the influence of extensive and costly government regulation; and
our estimates regarding future revenue, expenses capital requirements and the need for additional financing.

We believe these forward-looking statements are reasonable; however, these statements are only current predictions and are subject to known and unknown risks, uncertainties and other factors that may cause our or our industry's actual results, levels of activity, performance or achievements to be materially different from those anticipated by the forward-looking statements. We discuss or refer you to many of these risks in this prospectus in greater detail under the heading "Risk Factors" and elsewhere in this prospectus. Given these uncertainties, you should not rely upon forward-looking statements as predictions of future events.

All forward-looking statements attributable to us or persons acting on our behalf speak only as of the date hereof and are expressly qualified in their entirety by the cautionary statements included in this prospectus. We undertake no obligations to update or revise forward-looking statements to reflect events or circumstances that arise after the date made or to reflect the occurrence of unanticipated events, except as required by law. In evaluating forward-looking statements, you should consider these risks and uncertainties and not place undue reliance on our forward-looking statements.

3

PROSPECTUS SUMMARY

Our Business

We are a pre-clinical biotechnology company developing a novel and patented systemically-administered anti-cancer and anti-viral immunotherapy. Our technology has evolved from more than a century of immunotherapy advances. Our approach is based on the hypothesis that efficient activation of both innate and adaptive immune cells and associated anti-tumor and anti-viral immune responses will require a multi-targeted package of immune system activating signals that can be administered safely intravenously. Our patented technology is composed of single strains of attenuated and killed, non-pathogenic, Gram-negative bacteria, with reduced i.v. toxicity, but largely uncompromised ability to prime or activate many of the cellular components of innate and adaptive immunity. This approach has led to broad anti-tumor and anti-viral activity, including safe, durable anti-tumor response synergy with each of five different classes of existing agents, including checkpoint therapy, targeted antibody therapy and low-dose chemotherapy in pre-clinical models. Tumor eradication by our technology has demonstrated activation of both innate and adaptive immunological memory and, importantly, does not require provision of or targeting a tumor antigen in pre-clinical models. We have carried out successful GMP manufacturing of our lead clinical candidate, Decoy20, and completed other IND-enabling studies.

Unlike many competitor products, our technology does not depend on targeting with or to a specific antigen, providing broad applicability across multiple indications. Our product candidates are designed to have a much shorter half-life and produce less systemic exposure than small molecule, antibody or human cell-based therapies, potentially reducing the risk of non-specific auto-immune reactions. Our technology produces single agent activity and/or combination therapy-based durable responses of lymphoma, hepatocellular, colorectal and pancreatic tumors and has also produced significant single agent activity against chronic hepatitis B virus (HBV) and chronic human immunodeficiency virus (HIV) infections in pre-clinical models. In May 2022, the U.S. Food and Drug Administration cleared our Investigational New Drug, or IND, application for a Phase 1 clinical trial in patients with advanced solid tumors where currently approved therapies have failed and plan to commence a Phase 1 clinical trial in the second half of 2022 targeting solid tumors. Target indications include, but not limited to, colorectal, hepatocellular (± HBV), bladder, cervical and pancreatic carcinoma.

Decoy Merger

On August 3, 2021, we completed our merger with Decoy following the satisfaction or waiver of the conditions set forth in the Merger Agreement, dated as of March 15, 2021 among the Company, Decoy, Intec Israel, Domestication Merger Sub Ltd., an Israeli company and a wholly-owned subsidiary of the Company, or Domestication Merger Sub, and Dillon Merger Subsidiary Inc., a Delaware corporation and wholly owned subsidiary of the Company, or Merger Sub, pursuant to which Merger Sub merged with and into Decoy, with Decoy surviving as a wholly owned subsidiary of the Company, or the Merger, and the business conducted by Decoy became the business conducted by the combined company.

Previously, on July 27, 2021, we, Intec Israel and Domestication Merger Sub completed the previously announced domestication merger pursuant to the terms and conditions of the Domestication Merger Agreement, whereby Domestication Merger Sub merged with and into Intec Israel, with Intec Israel being the surviving entity and a wholly-owned subsidiary of ours. At the time of the Domestication Merger, Intec Israel continued to possess all of its assets, rights, powers and property as constituted immediately prior to the Domestication Merger and continued to be subject to all of its debts, liabilities and obligations as constituted immediately prior to the Domestication Merger.

Also, in connection with the Merger, we changed our name from "Intec Parent, Inc." to "Indaptus Therapeutics, Inc.".

Following completion of the Merger, our shares of common stock commenced trading at market open on August 4, 2021, on the Nasdaq Capital Market under the name "Indaptus Therapeutics, Inc." and ticker symbol "INDP" and under the new CUSIP 45339J 105.

Winding Down of Accordion Pill Business

In connection with the completion of the Merger, on August 4, 2021, our board of directors determined to wind down the Accordion Pill business of Intec Israel which was recently completed.

In connection with the winding down, we laid off all our employees and we terminated our contracts with counterparties, including the termination of the Process Development Agreement between Intec Israel and LTS Lohmann Therapie Systeme AG, and the termination of the unprotected lease agreement between Intec Israel and its landlord for the lease of offices located in Jerusalem, Israel.

4

Private Placement

In connection with the Merger, on July 23, 2021, we entered into a securities purchase agreement, or the Purchase Agreement, with a certain institutional investor, or the Purchaser, pursuant to which we agreed to sell and issue, in a private placement, or the Private Placement, a pre-funded warrant to purchase up to 2,727,273 shares of our common stock, or the Pre-funded Warrant, and a warrant to purchase up to 2,727,273 of our common stock at a purchase price of $10.99 per Pre-funded Warrant and associated Warrant, for aggregate gross proceeds to us of approximately $30.0 million, before deducting the placement agent's fees and other offering expenses payable by the Company. The Warrant has a term of five and one-half years, is exercisable immediately following the issuance date and has an exercise price of $11.00 per share, subject to adjustment as set forth therein.

On August 3, 2021, the Private Placement closed and in September 2021, the Pre-Funded Warrants were fully exercised. In addition, we issued to the placement agent a warrant to purchase 136,364 shares of our common stock at an exercise price of $13.75.

Corporate Information

Our principal executive offices are located at 3 Columbus Circle, 15th Floor, New York, NY 10019 and our telephone number is (646) 427-2727. Our website address is http://www.indaptusrx.com. The information contained on, or that can be accessed through, our website is neither a part of nor incorporated into this prospectus. We have included our website address in this prospectus solely as an inactive textual reference.

5

USE OF PROCEEDS

Unless otherwise indicated in an accompanying prospectus supplement, the net proceeds from the sale of securities will be used for our research and development costs, including the conduct of one or more clinical trials and process development and manufacturing, working capital and other general corporate purposes. Pending application of the net proceeds for the purposes as described above, we may invest the net proceeds in short-term, interest-bearing securities, investment grade securities, certificates of deposit or direct or guaranteed obligations of the U.S. government. When specific securities are offered, the prospectus supplement relating thereto will set forth our intended use of the net proceeds that we receive from the sale of such securities.

6

THE SECURITIES WE MAY OFFER

General

The descriptions of the securities contained in this prospectus, together with the applicable prospectus supplements, summarize all of the material terms and provisions of the various types of securities that we may offer. We will describe in the applicable prospectus supplement relating to any securities the particular terms of the securities offered by that prospectus supplement. If we indicate in the applicable prospectus supplement, the terms of the securities may differ from the terms we have summarized below. We may also include in the prospectus supplement information about material United States federal income tax considerations relating to the securities, and the securities exchange, if any, on which the securities will be listed.

We may sell from time to time, in one or more offerings:

common stock;
preferred stock;
subscription rights;
debt securities;
warrants;
units consisting of any combination of the securities listed above.

In this prospectus, we refer to the common stock, preferred stock, subscription rights, debt securities, warrants and units collectively as "securities." The total dollar amount of all securities that we may sell will not exceed $200,000,000.

If we issue debt securities at a discount from their original stated principal amount, then, for purposes of calculating the total dollar amount of all securities issued under this prospectus, we will treat the initial offering price of the debt securities as the total original principal amount of the debt securities.

This prospectus may not be used to consummate a sale of securities unless it is accompanied by a prospectus supplement.

7

DESCRIPTION OF CAPITAL STOCK

General

The following description of our capital stock is a summary. This summary is subject to the General Corporation Law of Delaware, or the DGCL, and the complete text of our Amended and Restated Certificate of Incorporation and Amended and Restated Bylaws.

Our authorized capital stock consists of shares made up of 200,000,000 shares of common stock, par value $0.01 per share and 5,000,000 shares of undesignated preferred stock, par value $0.01 per share.

Common stock

Each share of our common stock outstanding is entitled to one vote on all matters on which our stockholders generally are entitled to vote. However, holders of our common stock are not entitled to vote on any amendment to the Amended and Restated Certificate of Incorporation that relates solely to the terms of one or more outstanding classes or series of preferred stock if the holders of such affected classes or series are entitled, either separately or together with the holders of one or more other such class or series, to vote thereon pursuant to the Amended and Restated Certificate of Incorporation or the DGCL.

Generally, the Amended and Restated Bylaws provide that, subject to applicable law or the Amended and Restated Certificate of Incorporation and/or the Amended and Restated Bylaws, all corporate actions to be taken by vote of the stockholders are authorized by a majority of the votes cast by the stockholders entitled to vote thereon who are present in person, or by remote communication, if applicable, or represented by proxy, and where a separate vote by class or series is required, a majority of the votes cast by the stockholders of such class or series who are present in person, or by remote communication, if applicable, or represented by proxy will be the act of such class or series. Directors are elected by a plurality of the votes cast at a meeting of our stockholders for the election of directors at which a quorum is present.

Subject to the rights of holders of any then outstanding class or series of preferred stock, holders of our common stock are entitled to receive dividends and other distributions in cash, stock or property as the board of directors may declare thereon from time to time, and share equally on a per share basis in all such dividends and other distributions. In the event of our dissolution, whether voluntary or involuntary, after the payment in full of the amounts required to be paid to the holders of any outstanding class or series of preferred stock, our remaining assets and funds available for distribution will be distributed pro rata to the holders of our Common stock in proportion to the number of shares held by them and to the holders of any class or series of preferred stock entitled to a distribution. Holders of our Common stock do not have preemptive rights to purchase shares of our Common stock. All outstanding shares of our Common stock are fully paid and non- assessable. The rights, preferences and privileges of holders of our Common stock are subject to those of the holders of any outstanding class or series of our preferred stock that we may issue in the future.

Blank Check Preferred Stock

Our board of directors may, from time to time, authorize the issuance of one or more classes or series of preferred stock without stockholder approval. The Amended and Restated Certificate of Incorporation permits us to issue up to 5,000,000 shares of preferred stock. The number of authorized shares of preferred stock may be increased or decreased (but not below the number of shares thereof then outstanding) by the affirmative vote of the holders of a majority of our capital stock entitled to vote thereon, without a separate class vote of the holders of preferred stock, or any separate series votes of any series thereof, unless a vote of any such holders is required pursuant to the terms of any preferred stock certificate of designations.

Subject to the provisions of the Amended and Restated Certificate of Incorporation and limitations prescribed by law, our board of directors is expressly authorized, by resolution or resolutions, to provide, out of the unissued shares of preferred stock, for classes and series of preferred stock. The board of directors may fix the number of shares constituting such class or series and the designation of such class or series and the powers (including voting, if any), preferences and relative, participating, optional or other special rights, if any, and any qualifications, limitations or restrictions thereof, of the shares of such class or series. Each class or series is appropriately designated by a distinguishing designation prior to the issuance of any shares thereof. The powers (including voting, if any), preferences and relative, participating, optional and other special rights of each series of preferred stock, and the qualifications, limitations or restrictions thereof, if any, may differ from those of any and all other classes and series of preferred stock at any time outstanding.

8

The issuance of preferred stock, while providing flexibility in connection with possible acquisitions and other corporate purposes, may adversely affect the rights our common stockholders by, among other things:

restricting dividends on the common stock;
diluting the voting power of the common stock;
impairing the liquidation rights of the common stock; or
delaying or preventing a change in control without further action by the stockholders.

As a result of these or other factors, the issuance of preferred stock could have an adverse impact on the market price of our common stock. There is no current intention for us to issue any shares of preferred stock.

Anti-takeover Effects of Certain Provisions of the Amended and Restated Certificate of Incorporation and the Amended and Restated Bylaws

General

The Amended and Restated Certificate of Incorporation and Amended and Restated Bylaws contains provisions that are intended to enhance the likelihood of continuity and stability in the composition of our board of directors and that could make it more difficult to acquire control of us by means of a tender offer, open market purchases, a proxy contest or otherwise. A description of these provisions is set forth below.

Delaware Anti-Takeover Law

We are subject to Section 203 of the Delaware General Corporation Law. Section 203 generally prohibits a public Delaware corporation from engaging in a "business combination" with an "interested stockholder" for a period of three years after the date of the transaction in which the person became an interested stockholder, unless:

prior to the date of the transaction, the board of directors of the corporation approved either the business combination or the transaction which resulted in the stockholder becoming an interested stockholder;
upon consummation of the transaction that resulted in the stockholder becoming an interested stockholder, the interested stockholder owned at least 85% of the voting stock of the corporation outstanding at the time the transaction commenced, excluding specified shares; or
at or subsequent to the date of the transaction, the business combination is approved by the board of directors and authorized at an annual or special meeting of stockholders, and not by written consent, by the affirmative vote of at least 662/3% of the outstanding voting stock which is not owned by the interested stockholder.

Section 203 defines a "business combination" to include:

any merger or consolidation involving the corporation and the interested stockholder;
any sale, lease, exchange, mortgage, pledge, transfer or other disposition of 10% or more of the assets of the corporation to or with the interested stockholder;
subject to exceptions, any transaction that results in the issuance or transfer by the corporation of any stock of the corporation to the interested stockholder;
subject to exceptions, any transaction involving the corporation that has the effect of increasing the proportionate share of the stock of any class or series of the corporation beneficially owned by the interested stockholder; or
the receipt by the interested stockholder of the benefit of any loans, advances, guarantees, pledges or other financial benefits provided by or through the corporation.

In general, Section 203 defines an "interested stockholder" as any person that is:

the owner of 15% or more of the outstanding voting stock of the corporation;
9
an affiliate or associate of the corporation who was the owner of 15% or more of the outstanding voting stock of the corporation at any time within three years immediately prior to the relevant date; or
the affiliates and associates of the above.

Under specific circumstances, Section 203 makes it more difficult for an "interested stockholder" to effect various business combinations with a corporation for a three-year period, although the stockholders may, by adopting an amendment to the corporation's certificate of incorporation or bylaws, elect not to be governed by Section 203. The election not to be governed by Section 203 is effective (i) upon the filing of the certificate of amendment with the Secretary of State of the State of Delaware or the adoption of the amendment to the bylaws, as applicable, for a corporation that does not have a class of voting stock listed on a national securities exchange or held of record by more than 2,000 stockholders or (ii) 12 months after such action for all other corporations.

Our Amended and Restated Certificate of Incorporation and Amended and Restated Bylaws do not exclude us from the restrictions of Section 203. We anticipate that the provisions of Section 203 might encourage companies interested in acquiring us to negotiate in advance with its board of directors since the stockholder approval requirement would be avoided if a majority of the directors then in office approve either the business combination or the transaction that resulted in the stockholder becoming an interested stockholder.

No Cumulative Voting

Under Delaware law, the right to vote cumulatively does not exist unless the certificate of incorporation specifically authorizes cumulative voting. The Amended and Restated Certificate of Incorporation does not grant stockholders the right to vote cumulatively.

Blank Check Preferred Stock

We believe that the availability of the preferred stock under the Amended and Restated Certificate of Incorporation provides us with flexibility in addressing corporate issues that may arise. Having these authorized shares available for issuance allows us to issue shares of preferred stock without the expense and delay of a special stockholders' meeting. The authorized shares of preferred stock, as well as shares of common stock, is available for issuance without further action by our stockholders, with the exception of any actions required by applicable law or the rules of any stock exchange on which our securities may be listed. The board of directors has the power, subject to applicable law, to issue classes or series of preferred stock that could, depending on the terms of the class or series, impede the completion of a merger, tender offer or other takeover attempt.

Advance Notice Procedure

The Amended and Restated Bylaws provide an advance notice procedure for stockholders to nominate director candidates for election or to bring business before an annual meeting of stockholders, including proposed nominations of persons for election to the board of directors.

The Amended and Restated Bylaws provide that as to the notice of stockholder proposals of business to be brought at the annual meeting of stockholders, notice must be delivered to our secretary (i) not less than 90 days nor more than 120 days prior to the first anniversary of the preceding year's annual meeting or (ii) (x) if the date of the annual meeting is advanced by more than 30 days or delayed by more than 60 days from the first anniversary of the preceding year's annual meeting, or (y) with respect to the first annual meeting held after the issuance of securities pursuant to the registration statement of which this prospectus forms a part, not more than 120 days nor less than 90 days prior to the date of such annual meeting or, if later, the 10th day following the day on which public announcement of the date of such meeting is first made by us. In addition, any proposed business other than the nomination of persons for election to our board of directors must constitute a proper matter for stockholder action.

The Amended and Restated Bylaws provide that in the case of nominations for election at an annual meeting, notice must be delivered to, or mailed and received at, our principal executive offices (i) not less than 90 days nor more than 120 days prior to the first anniversary of the preceding year's annual meeting or (ii) (x) if the date of the annual meeting is advanced by more than 30 days or delayed by more than 60 days from the first anniversary of the preceding year's annual meeting, or (y) with respect to the first annual meeting held after the issuance of securities pursuant to the registration statement of which this prospectus forms a part, not more than 120 days nor less than 90 days prior to the date of such annual meeting or, if later, the 10th day following the day on which public announcement of the date of such annual meeting is first made by us. In the case of nominations for election at a special meeting of stockholders called for the election of directors, notice must be delivered to, or mailed and received at, our principal executive offices (i) not less than 90 days nor more than 120 days prior to the first anniversary of the preceding year's annual meeting or (ii) if later, the 10th day following the day on which public announcement of the date of such special meeting is first made by us. In addition, each such stockholder's notice must include certain information regarding the stockholder and the director nominee as set forth in the Amended and Restated Bylaws as described under the section entitled "Differences in Shareholder Rights."

10

Staggered Board

Our Amended and Restated Certificate of Incorporation provides that our board of directors is be divided into three classes of directors, with the classes as nearly equal in number as possible. At each annual meeting of the stockholders, a class of directors will be elected for a three-year term to succeed the directors of the same class whose terms are then expiring. As a result approximately one-third of our directors is elected each year. The initial term of office of the directors of Class I shall expire as of our first annual meeting of stockholders; the initial term of office of the directors of Class II shall expire as of our second annual meeting; and the initial term of office of the directors of Class III shall expire as of the third annual meeting of our stockholders.

The Class I directors are Hila Karah and Dr. Mark J. Gilbert;
The Class II directors are Anthony Maddaluna, Brian O'Callaghan and William B. Hayes; and
The Class III directors are Jeffrey A. Meckler, Michael J. Newman, Ph.D. and Dr. Roger J. Pomerantz.

Our Amended and Restated Certificate of Incorporation and Amended and Restated Bylaws provide that the number of directors shall be fixed from time to time by a resolution of the majority of its board of directors. Any additional directorships resulting from an increase in the number of directors will be distributed among the three classes so that, as nearly as possible, each class shall consist of one-third of the board of directors.

The division of our board of directors into three classes with staggered three-year terms may delay or prevent stockholder efforts to effect a change of its management or a change in control.

Action by Written Consent; Special Meetings of Stockholders

Our Amended and Restated Certificate of Incorporation provide that stockholder action can be taken only at an annual or special meeting of stockholders and cannot be taken by written consent in lieu of a meeting. Our Amended and Restated Certificate of Incorporation and Amended and Restated Bylaws provides that, except as otherwise required by law, special meetings of the stockholders can be called only by the board of directors, the chairperson of the board of directors, our chief executive officer or our president (in the absence of a chief executive officer). Except as provided above, our stockholders are not to be permitted to call a special meeting or to require the board of directors to call a special meeting.

Removal of Directors

Our Amended and Restated Certificate of Incorporation does not provide for the removal of directors by stockholders.

Exclusive Forum

Our Amended and Restated Certificate of Incorporation provide that unless we consent in writing to the selection of an alternative forum, the Court of Chancery of the State of Delaware shall be, to the fullest extent permitted by law, the sole and exclusive forum for any derivative action or proceeding brought on its behalf, any action asserting a claim for breach of a fiduciary duty owed by any of its directors and officers to it or its stockholders, any action asserting a claim arising pursuant to any provision of the DGCL, its Amended and Restated Certificate of Incorporation, its Amended and Restated Bylaws, or any action asserting a claim governed by the internal affairs doctrine. This exclusive forum provision would not apply to suits brought to enforce any liability or duty created by the Securities Act or the Exchange Act or any other claim for which the federal courts have exclusive jurisdiction. To the extent that any such claims may be based upon federal law claims, Section 27 of the Exchange Act creates exclusive federal jurisdiction over all suits brought to enforce any duty or liability created by the Exchange Act or the rules and regulations thereunder.

These choice of forum provisions may limit a stockholder's ability to bring a claim in a judicial forum that it finds favorable for disputes with us or its directors, officers or other team members, which may discourage such lawsuits against us and our directors, officers and other team members.

Federal Forum for Securities Act Claims

Section 22 of the Securities Act creates concurrent jurisdiction for federal and state courts over all suits brought to enforce any duty or liability created by the Securities Act or the rules and regulations thereunder. However, our Amended and Restated Certificate of Incorporation contains a federal forum provision which provides that unless we consent in writing to the selection of an alternative forum, the federal district courts of the United States of America will be the exclusive forum for the resolution of any complaint asserting a cause of action arising under the Securities Act. Any person or entity purchasing or otherwise acquiring any interest in our shares of capital stock are deemed to have notice of and consented to this provision. The Supreme Court of Delaware has held that this type of exclusive federal forum provision is enforceable. There may be uncertainty, however, as to whether courts of other jurisdictions would enforce such a provision, if applicable.

This choice of federal forum for Securities Act claims may limit a stockholder's ability to bring a claim in a judicial forum that it finds favorable, which may discourage such lawsuits against us and our directors, officers and other team members.

Stock Exchange Listing

Our common stock is traded on the Nasdaq Capital Market under the trading symbol "INDP."

Transfer Agent and Registrar

The transfer agent and registrar for our common stock is VStock Transfer, LLC, 18 Lafayette Pl, Woodmere, NY 11598.

11

DESCRIPTION OF SUBSCRIPTION RIGHTS

We may issue subscription rights to purchase our shares of common stock, preferred stock or debt securities. These subscription rights may be issued independently or together with any other security offered hereby and may or may not be transferable by the shareholder receiving the subscription rights in such offering. In connection with any offering of subscription rights, we may enter into a standby arrangement with one or more underwriters or other purchasers pursuant to which the underwriters or other purchasers may be required to purchase any securities remaining unsubscribed for after such offering.

The prospectus supplement relating to any subscription rights we offer will, to the extent applicable, include specific terms relating to the offering, including some or all of the following:

the price, if any, for the subscription rights;
the exercise price payable for each share upon the exercise of the subscription rights;
the number of subscription rights to be issued to each shareholder;
the number and terms of the shares which may be purchased per each subscription right;
the extent to which the subscription rights are transferable;
any other terms of the subscription rights, including the terms, procedures and limitations relating to the exchange and exercise of the subscription rights;
the date on which the right to exercise the subscription rights shall commence, and the date on which the subscription rights shall expire;
the extent to which the subscription rights may include an over-subscription privilege with respect to unsubscribed securities; and
if applicable, the material terms of any standby underwriting or purchase arrangement which may be entered into by us in connection with the offering of subscription rights.

The description in the applicable prospectus supplement of any subscription rights we offer will not necessarily be complete and will be qualified in its entirety by reference to the applicable subscription rights agreement, which will be filed with the SEC if we offer subscription rights. For more information on how you can obtain copies of the applicable subscription rights agreement if we offer subscription rights, see "Where You Can Find More Information" and "Incorporation of Certain Documents by Reference" beginning on page 31. We urge you to read the applicable subscription rights agreement and any applicable prospectus supplement in their entirety.

12

DESCRIPTION OF DEBT SECURITIES

General

We may issue senior and subordinated debt securities under indentures by and among us, certain of our subsidiaries, if any, and a trustee to be named in the senior indenture, as the indenture trustee. Each indenture will be subject to, and governed by, the Trust Indenture Act of 1939, as amended, or the Trust Indenture Act, and we may supplement the indenture from time to time.

This prospectus summarizes the material provisions of the indentures and the debt securities that we may issue under the indentures. This summary is not complete and may not describe all of the provisions of the indentures or of any of the debt securities that might be important to you. For additional information, you should carefully read the forms of indenture and debt securities that are filed as exhibits to the registration statement of which this prospectus forms a part and any definitive indentures, supplemental indentures and forms of debt securities that are incorporated by reference as exhibits to such registration statement.

When we offer to sell a particular series of debt securities, we will describe the specific terms of those debt securities in a supplement to this prospectus. We will also indicate in the supplement whether the general terms in this prospectus apply to a particular series of debt securities. Accordingly, for a description of the terms of a particular issue of debt securities, you should carefully read both this prospectus and the applicable supplement.

In the summary below, we have included references to the section numbers of the indentures so that you can easily locate the related provisions in the indentures for additional detail. You should also refer to the applicable indenture for the definitions of any capitalized terms that we use below but do not define in this prospectus. When we refer to particular sections of the indentures or to defined terms in the indentures, we intend to incorporate by reference those sections and defined terms into this prospectus.

Terms

The debt securities will be our direct obligations. The amount of debt securities we may offer under this prospectus is unlimited as to principal amount. We may issue the debt securities, from time to time and in one or more series, established in or pursuant to authority granted by one or more resolutions of our board of directors, and set forth in, or determined in the manner provided in, an officers' certificate, or established in one or more supplemental indentures. We may issue debt securities with terms different from those of our previously issued debt securities.

Each indenture provides that there may be more than one trustee under such indenture, each such trustee with respect to one or more series of debt securities. Any trustee under the indentures may resign or be removed with respect to one or more series of debt securities, and a successor trustee may be appointed to act with respect to that series. If two or more persons act as trustee with respect to different series of debt securities, each trustee shall be a trustee of a trust under that indenture separate and apart from the trust administered by any other trustee. Except as otherwise indicated in this prospectus, each trustee may take any action described in this prospectus only with respect to the one or more series of debt securities for which it is trustee under the relevant indenture.

You should refer to the applicable supplement to this prospectus relating to a particular series of debt securities for the specific terms of the debt securities, including, but not limited to:

the title of the debt securities, whether the debt securities will be guaranteed and the identity of the guarantor or guarantors, if any;
the total principal amount of the debt securities and any limit on the total principal amount;
the price, expressed as a percentage of the principal amount of the debt securities, at which we will issue the debt securities and any portion of the principal amount payable upon acceleration of the debt securities;
the terms, if any, by which holders of the debt securities may convert or exchange the debt securities for our shares of common stock, or any of our other securities or property;
if the debt securities are convertible or exchangeable, any limitations on the ownership or transferability of the securities or property into which holders may convert or exchange the debt securities;
13
the date or dates, or the method for determining the date or dates, on which we will be obligated to pay the principal of the debt securities and the amount of principal we will be obligated to pay;
the rate or rates, which may be fixed or variable, at which the debt securities of the series will bear interest, if any, or the method by which the rate or rates will be determined;
whether the debt securities rank as senior, senior subordinated or subordinated or any combination thereof and the terms of any subordination;
the date or dates, or the method for determining the date or dates, from which any interest will accrue on the debt securities, the dates on which we will be obligated to pay any interest, the regular record dates, if any, for the interest payments, or the method by which the dates will be determined, the persons to whom we will be obligated to pay interest and the basis upon which interest will be calculated, if other than that of a 360-day year consisting of twelve 30-day months;
the place or places where the principal of, and any premium, make-whole amount, interest or additional amounts on, the debt securities will be payable, where the holders of the debt securities may surrender their debt securities for conversion, transfer or exchange, and where the holders may serve notices or demands to us in respect of the debt securities and the indenture];
whether the debt securities will be in registered or bearer form, and the terms and conditions relating to the form, and, if in registered form, the denominations in which we will issue the debt securities if other than $1,000 or a multiple of $1,000 and, if in bearer form, the denominations in which we will issue the debt securities if other than $5,000;
the identity of the trustee of the debt securities of the series and, if other than the trustee, the identity of each security registrar and/or paying agent for debt securities of the series;
the period or periods during which the price or prices, including any premium at which, the currency or currencies in which, and the other terms and conditions upon which, we may redeem the debt securities at our option, if we have such an option;
any obligation that we have to redeem, repay or purchase debt securities under any sinking fund or similar provision or at the option of a holder of debt securities and the terms and conditions upon which we will redeem, repay or purchase all or a portion of the debt securities under that obligation;
the currency or currencies in which we will sell the debt securities and in which the debt securities will be denominated and payable;
whether the amount of payment of principal of, and any premium, make-whole amount or interest on, the debt securities of the series may be determined with reference to an index, formula or other method and the manner in which the amounts will be determined;
whether the principal of, and any premium, make-whole amount, additional amounts or interest on, the debt securities of the series are to be payable, at our election or at the election of a holder of the debt securities, in a currency or currencies other than that in which the debt securities are denominated or stated to be payable, the period or periods during which, and the terms and conditions upon which, this election may be made, and the time and manner of, and identity of the exchange rate agent responsible for, determining the exchange rate between the currency or currencies in which the debt securities are denominated or stated to be payable and the currency or currencies in which the debt securities will be payable;
the designation of the initial exchange rate agent, if any, or any depositaries;
any provisions granting special rights to the holders of the debt securities of the series at the occurrence of named events;
any additions to, modifications of or deletions from the terms of the debt securities with respect to the events of default or covenants contained in the indenture;
14
whether the debt securities of the series will be issued in certificated or book-entry form and the related terms and conditions, including whether any debt securities will be issued in temporary and/or permanent global form, and if so, whether the owners of interests in any permanent global debt security may exchange those interests for debt securities of that series and of like tenor of any authorized form and denomination and the circumstances under which any exchanges may occur, if other than in the manner provided in the indenture, and, if debt securities of or within the series are to be issuable as a global debt security, the identity of the depositary for such series;
the date as of which any bearer securities, and/or temporary global debt security representing outstanding securities of or within the series will be dated if other than the date of original issuance of the first debt security of the series to be issued;
if the debt securities will be issued in definitive form only upon our receipt, or the trustee's receipt, of certificates or other documents, or upon the satisfaction of conditions, a description of those certificates, documents or conditions;
if the debt securities will be issued upon the exercise of debt warrants, the time, manner and place for the debt securities to be authenticated and delivered;
the applicability, if any, of the defeasance and covenant defeasance provisions of the indenture, as described below under "Modification of the Indentures-Discharge, Defeasance and Covenant Defeasance";
any applicable U.S. federal income tax consequences, including whether and under what circumstances we will pay any additional amounts, as contemplated in the indenture on the debt securities, to any holder who is not a U.S. person in respect of any tax, assessment or governmental charge withheld or deducted and, if we will pay additional amounts, whether, and on what terms, we will have the option to redeem the debt securities in lieu of paying the additional amounts;
the provisions, if any, relating to any security provided for the debt securities of the series;
any other covenant or warranty included for the benefit of the debt securities of the series;
any proposed listing of the debt securities on any securities exchange or market; and
any other terms of the debt securities or of any guarantees issued in connection with the debt securities not inconsistent with the provisions of the indenture.

The debt securities may provide for our payment of less than their entire principal amount if their maturity is accelerated as a result of the occurrence and continuation of an event of default. If this is the case, the debt securities would have what is referred to as "original issue discount." Any special U.S. federal income tax, accounting and other considerations applicable to original issue discount securities will be described in the applicable prospectus supplement.

We may issue debt securities from time to time, with the principal amount payable on any principal payment date, or the amount of interest payable on any interest payment date, to be determined by reference to one or more currencies or currency exchange rates, commodity prices, equity indices or other factors. Holders of debt securities with these features may receive payment of a principal amount on any principal payment date, or a payment of interest on any interest payment date, that is greater than or less than the amount of principal or interest otherwise payable on the applicable dates, depending upon the value on those dates of the applicable currencies or currency exchange rates, commodity prices, equity indices or other factors.

Information as to the methods for determining the amount of principal or interest payable on any date, the currencies or currency exchange rates, commodity prices, equity indices or other factors to which the amount payable on that date is linked and additional tax considerations will be included in the applicable prospectus supplement. All debt securities of any one series will be substantially identical, except as to denomination and except as may otherwise be provided by an officers' certificate or in any supplement to the applicable indenture. We are not required to issue all of the debt securities of a series at the same time, and, unless otherwise provided in the applicable indenture, supplemental indenture or officers' certificate, we may re-open a series without the consent of the holders of the debt securities of that series to issue additional debt securities of that series.

The indentures do not contain any provisions that limit our ability to incur indebtedness or that would protect holders of debt securities in the event we become a party to a highly-leveraged or similar transaction in which we would incur or acquire a large amount of additional debt, but such provisions may appear in the applicable prospectus supplement. You should refer to the applicable prospectus supplement for information regarding any deletions from, modifications of or additions to the events of default or covenants that are described below, including any addition of a covenant or other provision providing event risk or similar protection.

15

Guarantees

Debt securities may be issued and unconditionally and irrevocably guaranteed by us or certain of our subsidiaries, if any, that are listed as guarantors in the applicable supplement to this prospectus. Any guarantee would cover the timely payment of the principal of, and any premium, make-whole amount, interest or sinking fund payments on, the debt securities, whether we make the payment at a maturity date, as a result of acceleration or redemption or otherwise. We will more fully describe the existence and terms of any guarantee of any of our debt securities by us or our subsidiaries in the prospectus supplement relating to those debt securities.

Denominations, Interest, Registration and Transfer

Unless the applicable prospectus supplement states otherwise, any debt securities of any series that we issue in registered form will be issued in denominations of $1,000 and multiples of $1,000, and debt securities of any series that we issue in bearer form will be issued in denominations of $5,000.

Unless the applicable prospectus supplement states otherwise, the principal of, and any premium, make-whole amount or interest on, any series of debt securities will be payable in the currency designated in the prospectus supplement at the corporate trust office of the trustee, initially, the corporate trust office of the trustee to be named in the senior indenture. At our option, however, payment of interest may be made by check mailed to the address of the person entitled to the interest payment as it appears in the security register for the series or by wire transfer of funds to that person at an account maintained within the United States. We may at any time designate additional paying agents or rescind designation of any paying agents or approve a change in the office through which any paying agent acts, except that we will be required to maintain a paying agent in each place of payment for any series. All monies that we pay to a paying agent for the payment of any principal of, or any premium, make-whole amount, interest or additional amounts on, any debt security which remains unclaimed at the end of two years after that payment became due and payable will be repaid to us. After that time, the holder of the debt security will be able to look only to us for payment.

Any interest that we do not punctually pay on any interest payment date with respect to a debt security will cease to be payable to the holder on the applicable regular record date and may either:

be paid to the holder at the close of business on a Special Record Date for the payment of defaulted interest, to be determined by the trustee; or
be paid at any time in any other lawful manner, as more fully described in the indentures.

Subject to certain limitations imposed upon debt securities issued in book-entry form, debt securities of any series will be exchangeable for other debt securities of the same series and of the same total principal amount and authorized denomination upon the surrender of the debt securities at the corporate trust office of the trustee. In addition, subject to certain limitations imposed upon debt securities issued in book-entry form, the debt securities of any series may be surrendered for conversion, transfer or exchange at the corporate trust office of the trustee. Every debt security surrendered for conversion, transfer or exchange must be duly endorsed or accompanied by a written instrument of transfer. There will be no service charge for any transfer or exchange of any debt securities, but we may require holders to pay any tax or other governmental charge payable in connection with the transfer or exchange.

If the applicable prospectus supplement refers to us designating any transfer agent for any series of debt securities, in addition to the trustee, we may at any time remove the transfer agent or approve a change in the location at which the transfer agent acts, except that we will be required to maintain a transfer agent in each place of payment for any series of debt securities. We may at any time designate additional transfer agents with respect to any series of debt securities.

Neither we nor any trustee will be required to do any of the following:

issue, register the transfer of or exchange debt securities of any series during a period beginning at the opening of 15 business days before there is a selection of debt securities of that series to be redeemed and ending at the close of business on the day of mailing or publication of the relevant notice of redemption;
16
register the transfer of or exchange any debt security, or portion thereof, called for redemption, except the unredeemed portion of any debt security being only partially redeemed;
exchange any debt security in bearer form that is selected for redemption, except that a debt security in bearer form may be exchanged for a debt security in registered form of that series and like denomination, provided that the debt security in registered form must be simultaneously surrendered for redemption; or
issue or register the transfer or exchange of any debt security that has been surrendered for repayment at the option of the holder, except the portion, if any, of the debt security that will not be partially or entirely repaid.

Global Debt Securities

The debt securities of a series may be issued in the form of one or more fully registered global securities that will be deposited with a depositary or with a custodian for a depositary identified in the prospectus supplement relating to the series and registered in the name of the depositary or its nominee. In this case, we will issue one or more global securities in a denomination or total denominations equal to the portion of the total principal amount of outstanding registered debt securities of the series to be represented by the global security or securities. We expect that any global securities issued in the United States would be deposited with The Depositary Trust Company, as depositary or its custodian. We may issue any global securities in fully registered form on a temporary or permanent basis. Unless and until a global security is exchanged for debt securities in definitive registered form, a permanent global security may not be transferred except as a whole by the depositary to its nominee or by a nominee to the depositary or another nominee, or by the depositary or its nominee to a successor of the depositary or the successor depositary's nominee.

The specific terms of the depositary arrangement with respect to any series of debt securities to be represented by a registered global security will be described in the applicable prospectus supplement. We anticipate that the following provisions will apply to depositary arrangements.

Ownership of beneficial interests in a global security will be limited to persons that have accounts with, or are participants of, the depositary for the registered global security, or persons that may hold interests through participants. When we issue a registered global security, the depositary will credit, on its book-entry registration and transfer system, the participants' accounts with the respective principal amounts of the debt securities represented by the global security owned by those participants. The accounts to be credited will be designated by any dealers, underwriters or agents participating in an offering of the debt securities, or by us or the trustee if we are directly offering the debt securities. The participants' ownership, and any transfer, of a registered global security will be shown on records maintained by the depositary, and ownership of persons who hold debt securities through participants will be reflected on the records of the participants. State and federal laws may impair a person's ability to own, transfer or pledge interests in a registered global security.

So long as the depositary or its nominee is the registered owner of the global security, the depositary or its nominee, as the case may be, will be considered the sole owner or holder of the debt securities represented by the global security for all purposes under the applicable indenture. Except as set forth below, owners of beneficial interests in a global security will not be entitled to have the debt securities represented by the registered global security registered in their names, will not receive or be entitled to receive physical delivery of the debt securities in definitive form and will not be considered the owners or holders of the debt securities under the applicable indenture. Accordingly, each person owning a beneficial interest in a registered global security must rely on the depositary's procedures and, if that person is not a participant, on the procedures of the participant through which that person owns its interest to exercise any rights of a holder under the applicable indenture. We understand that under existing industry practices, if we request any action of holders or if an owner of a beneficial interest in a registered global security desires to give or take any action which a holder is entitled to give or take under the applicable indenture, the depositary would authorize the participants holding the relevant beneficial interests to give or take the action, and the participants would authorize beneficial owners owning through those participants to give or take the action or would otherwise act upon the instructions of beneficial owners holding through them.

Payments of principal of, and any premium, make-whole amount, interest or additional amounts on a registered global security will be made to the depositary or its nominee, as the case may be, as the registered owner of the global security. Neither we, the trustee, the paying agent nor the registrar, nor any other agent of ours or of the trustee, will have any responsibility or liability for any aspect of the records relating to, or payments made on account of, beneficial ownership interests in the global security or for maintaining, supervising or reviewing any records relating to the beneficial ownership interests.

17

We expect that once the depositary receives any payment of principal of, any premium, make-whole amount, interest or additional amount on, a registered global security, the depositary will immediately credit the participants' accounts with payments in amounts proportionate to their respective beneficial interests in the global security, as shown on the records of the depositary. We also expect that payments by the participants to owners of beneficial interests in the registered global security held through the participants will be governed by standing customer instructions and customary practices, as is now the case with the securities held for the accounts of customers in bearer form or registered in "street name," and will be the responsibility of the participants.

If the depositary is at any time unwilling or unable to continue as depositary or ceases to be a clearing agency under the Securities Exchange Act of 1934, as amended, or the Exchange Act, and we do not appoint a successor depositary within 90 days, we will issue debt securities in definitive form in exchange for the registered global security. In addition, we may at any time and in our sole discretion decide not to have any of the debt securities of a series represented by one or more global securities, and, in such event, we will issue debt securities in definitive form in exchange for all of the global security or securities representing the debt securities. We will register any debt securities issued in definitive form in exchange for a global security in the name or names that the depositary provides to the trustee. We expect that those names will be based upon directions received by the depositary from the participants with respect to ownership of beneficial interests in the global security.

Debt securities in bearer form may also be issued in the form of one or more global securities that will be deposited with a common depositary for Euroclear and Clearstream, or with a nominee for the depositary identified in the applicable prospectus supplement. We will describe in the applicable prospectus supplement the specific terms and procedures of the depositary arrangement, including the specific terms of the depositary arrangement and any specific procedures, for the issuance of debt securities in definitive form in exchange for a global security in bearer form, with respect to any portion of a series of debt securities to be represented by a global security in bearer form.

Merger, Consolidation or Sale

We may consolidate with, or sell, lease or convey all or substantially all of our assets to, or merge with or into, any other corporation, trust or entity provided that:

we are the survivor in the transaction, or the survivor, if not us, is an entity organized under the laws of the United States or a state of the United States, or the State of Israel, which entity expressly assumes by supplemental indenture the due and punctual payment of the principal of, and any premium, make-whole amount, interest and additional amounts on, all of the outstanding debt securities and the due and punctual performance and observance of all of the covenants and conditions contained in the indenture;
immediately after giving effect to the transaction and treating any indebtedness that becomes an obligation of ours or one of our subsidiaries as a result of the transaction as having been incurred by us or our subsidiary at the time of the transaction, there is no event of default under the applicable indenture and no event which, after notice or the lapse of time, or both, would become an event of default; and
we deliver an officers' certificate and an opinion of our legal counsel, each as to the satisfaction of conditions contained in the applicable indenture.

This covenant would not apply to any recapitalization transaction, a change of control of us or a transaction in which we incur a large amount of additional debt, unless the transactions or change of control included a merger, consolidation or transfer or lease of substantially all of our assets. Except as may be described in the applicable prospectus supplement, there are no covenants or other provisions in the indentures providing for a "put" right or increased interest or that would otherwise afford holders of debt securities additional protection in the event of a recapitalization transaction, a change of control of us or a transaction in which we incur a large amount of additional debt.

18

Certain Covenants

Provision of Financial Information

Whether or not we are subject to Section 13 or 15(d) of the Exchange Act, we will file annual reports and other documents with the SEC pursuant to Sections 13 and 15(d) of the Exchange Act as if we were so subject, on or prior to the dates by which we are or would have been required to file those documents if we were so subject. In any event, we will:

file with the applicable trustee copies of the annual reports and other documents that we are or would be required to file with the SEC under Sections 13 and 15(d) of the Exchange Act within 15 days of each of the respective dates by which we are or would have been required to file those reports with the SEC; and
promptly upon written request and payment of the reasonable cost of duplication and delivery, supply copies of those documents to holders and any prospective holders of debt securities if filing those documents with the SEC is not permitted under the Exchange Act.

Additional Covenants

Any additional covenants with respect to any series of debt securities will be described in the applicable prospectus supplement.

Events of Default, Notice and Waiver

Except as otherwise provided in the applicable prospectus supplement, the following events are "events of default" with respect to any series of debt securities that we may issue under the indentures:

we fail for 30 days to pay any installment of interest or any additional amounts payable on any debt security of that series;
we fail to pay the principal of, or any premium or make-whole amount on, any debt security of that series when due, either at maturity, redemption or otherwise;
we fail to make any sinking fund payment as required for any debt security of that series;
we breach or fail to perform any covenant or warranty contained in the applicable indenture, other than a covenant added solely for the benefit of a different series of debt securities issued under the applicable indenture or except as otherwise provided for in the applicable indenture, and our breach or failure to perform continues for 60 days after we have received written notice in accordance with the applicable indenture of our breach or failure to perform;
we default under a bond, debenture, note, mortgage, indenture or instrument evidencing indebtedness for money borrowed by us, or by any subsidiaries of ours that we have guaranteed or for which we are directly responsible or liable as obligor or guarantor, that has a principal amount outstanding of $20,000,000 or more, other than indebtedness which is non-recourse to us or our subsidiaries, which default has caused the indebtedness to become due and payable earlier than it would otherwise have become due and payable, and the indebtedness has not been discharged or the acceleration has not been rescinded or annulled, within 30 days after written notice was provided to us in accordance with the applicable indenture;
the bankruptcy, insolvency or reorganization or court appointment of a receiver, liquidator or appointment of a trustee for us or of any of our Significant Subsidiaries, or for all or substantially all of our properties or the properties of our Significant Subsidiaries; and
any other event of default described in the applicable prospectus supplement and indenture.
19

If there is a continuing event of default with respect to outstanding debt securities of a series, then the trustee or the holders of not less than 25% in aggregate principal amount of the outstanding debt securities of that series, voting as a single class, may declare immediately due and payable the principal amount or other amount as may be specified by the terms of those debt securities and any premium or make-whole amount on the debt securities of that series; provided, however, that upon the occurrence and continuation of certain defaults related to bankruptcy or insolvency, the principal (or, if any debt securities are Original Issue Discount Securities or Indexed Securities, such portion of the principal as may be specified in the terms thereof) of, and the Make-Whole Amount, if any, on, all the outstanding debt securities of that series and any accrued interest through the occurrence of such Event of Default, shall become due and payable immediately, without any declaration or other act by the trustee or any other holder. However, at any time after an acceleration with respect to debt securities of a series has been made, but before a judgment or decree for payment of the money due has been obtained by the trustee, the holders of not less than a majority in principal amount of the outstanding debt securities of that series may cancel the acceleration and annul its consequences if:

we pay or deposit with the trustee all required payments of the principal of, and any premium, make-whole amount, interest, and additional amounts on, the applicable series of debt securities, plus fees, expenses, disbursements and advances of the trustee; and
all events of default, other than the nonpayment of accelerated principal, premium, or interest, with respect to the applicable series of debt securities have been cured or waived as provided in the indentures.

The indentures also provide that the holders of not less than a majority in principal amount of the outstanding debt securities of any series may waive any past default with respect to that series and its consequences (except in respect of certain events of default related to bankruptcy or insolvency, the waiver of which requires approval of a majority in principal amount of all outstanding debt securities under the applicable indenture), except a default involving:

our failure to pay the principal of, and any premium, make-whole amount, interest or additional amounts on, any debt security; or
a covenant or provision contained in the applicable indenture that cannot be modified or amended without the consent of the holders of each outstanding debt security affected by the default.

The trustee is generally required to give notice to the holders of debt securities of each affected series within 90 days of a default actually known to a Responsible Officer of the trustee unless the default has been cured or waived. The trustee may, however, withhold notice of default if the Responsible Officers of the trustee in good faith determine that the withholding of such notice is in the interests of the holders of the debt securities of that series unless the default relates to:

our failure to pay the principal of, and any premium, make-whole amount, interest or additional amounts on, any debt security of that series; or
any sinking fund installment for any debt securities of that series.

Each indenture provides that no holder of debt securities of any series may institute a proceeding with respect to the indenture or for any remedy under the indenture, unless the trustee fails to act for 60 days after it has received a written notice of a continuing event of default with respect to the debt securities of that series from such holder and a written request to institute proceedings in respect of an event of default from the holders of not less than 25% in principal amount of the outstanding debt securities of that series (except in respect of certain events of default related to bankruptcy or insolvency, which requires the written request of not less than 25% in principal amount of all outstanding debt securities under the applicable indenture), as well as an offer of indemnity satisfactory to the trustee; provided, that no direction inconsistent with such request has been given to the trustee during such 60-day period by the holders of a majority in principal amount of outstanding debt securities of that series. This provision will not prevent, however, any holder of debt securities from instituting suit for the enforcement of payment of the principal of, and any premium, make-whole amount, interest or additional amounts on, the debt securities at their respective due dates.

Subject to provisions in each indenture relating to the trustee's duties in case of default, the trustee is not under an obligation to exercise any of its rights or powers under the indenture at the request or direction of any holders of any series of debt securities then outstanding, unless the holders have offered to the trustee security or indemnity satisfactory to it. Subject to these provisions for the indemnification of the trustee, the holders of not less than a majority in principal amount of all outstanding debt securities under the applicable indenture will have the right to direct the time, method and place of conducting any proceeding for any remedy available to the trustee, or of exercising any trust or power conferred upon the trustee. The trustee may, however, refuse to follow any direction which conflicts with any law or the applicable indenture, which may involve the trustee in personal liability or which may be unduly prejudicial to the holders of debt securities of the applicable series not joining in the direction.

20

Within 120 days after the close of each fiscal year, we must deliver to the trustee a certificate, signed by one of several specified officers, stating that officer's knowledge of our compliance with all the conditions and covenants under the applicable indenture, and, in the event of any noncompliance, specifying the noncompliance and the nature and status of the noncompliance.

Modification of the Indentures

Modification Without Consent of the Holders

Together with the trustee, we may, when authorized by our Board of Directors, modify each of the indentures without the consent of any holder of debt securities for any of the following purposes:

to evidence the succession of another person to us as obligor under the indenture;
to add to our existing covenants additional covenants for the benefit of the holders of all or any series of debt securities, or to surrender any right or power conferred upon us in the indenture;
to add events of default for the benefit of the holders of all or any series of debt securities;
to add or change any provisions of the indenture to facilitate the issuance of, or to liberalize the terms of, debt securities in bearer form, or to permit or facilitate the issuance of debt securities in uncertificated form, provided that this action will not adversely affect the interests of the holders of the debt securities of any series in any material respect;
to add, change or eliminate any provisions of the indenture, provided that any addition, change or elimination shall neither apply to any debt security of any series created prior to the execution of such supplemental indenture and entitled to the benefit of such provision nor modify the rights of the holder of any debt security with respect to such provision or become effective only when there are no outstanding debt securities;
to secure previously unsecured debt securities;
to establish the form or terms of debt securities of any series, including the provisions and procedures, if applicable, for the conversion or exchange of the debt securities into our shares of common stock or other securities or property;
to evidence and provide for the acceptance or appointment of a successor trustee or facilitate the administration of the trusts under the indenture by more than one trustee;
to make any provision with respect to the conversion or exchange of rights of holders pursuant to the requirements of the indenture;
to cure any ambiguity, defect or inconsistency in the indenture, provided that the action does not adversely affect the interests of holders of debt securities of any series issued under the indenture;
to close the indenture with respect to the authentication and delivery of additional series of debt securities or to qualify, or maintain qualification of, the indenture under the Trust Indenture Act; or
to supplement any of the provisions of the indenture to the extent necessary to permit or facilitate defeasance and discharge of any series of debt securities, provided that the action shall not adversely affect the interests of the holders of the debt securities of any series in any material respect.
21

Modification With Consent of Holders

Together with the trustee, we may, when authorized by our Board of Directors, also make modifications and amendments to each indenture with the consent of the holders of a majority in principal amount of the outstanding debt securities of all affected series. Without the consent of each affected holder, however, no modification to either indenture may:

change the stated maturity of the principal of, or any premium, make-whole amount or installment of principal of, or interest on, any debt security;
reduce the principal amount of, or the rate or amount of interest on, or any premium or make-whole amount payable on redemption of, or any additional amounts payable with respect to, any debt security or change any obligation to pay additional amounts except as permitted by the indenture;
reduce the amount of principal of an original issue discount security or make-whole amount that would be due and payable upon declaration of acceleration of the maturity of the original discount or other security, or would be provable in bankruptcy, or adversely affect any right of repayment of the holder of any debt security;
change the place of payment or the currency or currencies of payment of the principal of, and any premium, make-whole amount, interest, or additional amounts on, any debt security;
impair the right to institute suit for the enforcement of any payment on or with respect to any debt security;
reduce the percentage of the holders of outstanding debt securities of any series necessary to modify or amend the indenture, to waive compliance with provisions of the indenture or defaults and their consequences under the indenture, or to reduce the quorum or voting requirements contained in the indenture;
make any change that adversely affects the right to convert or exchange any debt security other than as permitted by the indenture or decrease the conversion or exchange rate or increase the conversion or exchange price of any such debt security; or
modify any of the foregoing provisions or any of the provisions relating to the waiver of past defaults or covenants, except to increase the required percentage of holders necessary to effect that action or to provide that other provisions may not be modified or waived without the consent of the holder of the debt security.

Documentation

Any modification or amendment of an indenture, whether effected with or without the consent of any holder, will be documented in a supplemental indenture.

Discharge, Defeasance and Covenant Defeasance

Unless the terms of a series of debt securities provide otherwise, under the indentures, we may discharge some of our respective obligations to holders of any series of debt securities that:

have not already been delivered to the trustee for cancellation and that either have become due and payable or will become due and payable within one year; or
are scheduled for redemption within one year.

We can discharge these obligations by irrevocably depositing with the trustee funds in the currency or currencies in which the debt securities are payable in an amount sufficient to pay and discharge the entire indebtedness on those debt securities, including principal of, and any premium, make-whole amount, interest and additional amounts on, the debt securities on and up to the date of such deposit, or, if the debt securities have become due and payable, on and up to the stated maturity or redemption date, as the case may be.

In addition, if the terms of the debt securities of a series permit us to do so, we may elect either of the following:

to defease and be discharged from any and all obligations with respect to the debt securities, except, among other things, our obligations to the holders of Outstanding Securities;
pay any additional amounts upon the occurrence of several particular tax and other events;
pay the fees, expenses and indemnitees of the trustee;
22
register the transfer or exchange of the debt securities;
replace temporary or mutilated, destroyed, lost or stolen debt securities;
maintain an office or agency for the debt securities; and
hold monies for payment in trust; or
to be released from our obligations with respect to the debt securities under sections of the applicable indenture described under "Certain Covenants" or, if permitted by the terms of the debt securities, our obligations with respect to any other covenant.

If we choose to be released from our respective obligations under the covenants, any failure to comply with any of the obligations imposed on us by the covenants will not constitute a default or an event of default with respect to the debt securities. However, to make either election, we must irrevocably deposit with the trustee an amount, in such currency or currencies in which the debt securities are payable at their stated maturity, or in Government Obligations, or both, that will provide sufficient funds to pay the principal of, and any premium, make-whole amount, interest and additional amounts on, the debt securities, and any mandatory sinking fund or similar payments on the debt securities, on the relevant scheduled due dates.

We may defease and discharge the obligations, as described in the preceding paragraphs, only if, among other things, we have delivered to the trustee an opinion of counsel to the effect that:

the holders of the debt securities will not recognize income, gain or loss for U.S. federal income tax purposes as a result of the defeasance or covenant defeasance described in the previous paragraphs and will be subject to U.S. federal income tax on the same amounts, in the same manner and at the same times as would have been the case if the defeasance or covenant defeasance had not occurred; and
in the case of defeasance, the opinion of counsel must refer to, and be based upon, a ruling of the Internal Revenue Service, or IRS, or a change in applicable U.S. federal income tax laws occurring after the date of the applicable indenture.

Unless otherwise provided in the applicable prospectus supplement, if, after we have deposited funds and/or Government Obligations to effect defeasance or covenant defeasance with respect to debt securities of any series:

the holder of a debt security of the series elects to receive payment in a currency other than that in which the deposit has been made in respect of the debt security; or
a conversion event, as defined below, occurs in respect of the currency in which the deposit has been made,

then the indebtedness represented by the debt security will be fully discharged and satisfied through the payment of the principal of, and any premium, make-whole amount and interest on, the debt security as they become due, and additional amounts, if any, out of the proceeds yielded by converting the amount deposited in respect of the debt security into the currency in which the debt security becomes payable as a result of the holder's election or the conversion event based on the applicable market exchange rate.

Unless otherwise provided in the applicable prospectus supplement, a "conversion event" means the cessation of use of:

a currency issued by the government of one or more countries other than the United States, both by the government of the country that issued that currency and for the settlement of transactions by a central bank or other public institutions of or within the international banking community;
the European Community, both within the European Monetary System and, for the settlement of transactions, by public institutions of or within the European Community; or
any currency for the purposes for which it was established.

Unless otherwise provided in the applicable prospectus supplement, we will make all payments of principal of, and any premium, make-whole amount, interest and additional amounts on, any debt security that is payable in a foreign currency that ceases to be used by its government of issuance in United States dollars.

23

In the event that we effect covenant defeasance with respect to any debt securities and the debt securities are declared due and payable because of the occurrence of an event of default other than:

the event of default described in the fourth bullet under "Certain Covenants-Events of Default, Notice and Waiver," which would no longer be applicable to the debt securities of that series; or
the event of default described in the sixth bullet under "Certain Covenants-Events of Default, Notice and Waiver" with respect to a covenant as to which there has been covenant defeasance,

then the amount on deposit with the trustee will still be sufficient to pay amounts due on the debt securities at the time of their stated maturity but may not be sufficient to pay amounts due on the debt securities at the time of the acceleration resulting from the event of default. In this case, we would remain liable to make payment of the amounts due at the time of acceleration.

The applicable prospectus supplement may describe any additional provisions permitting defeasance or covenant defeasance, including any modifications to the provisions described above, with respect to a particular series of debt securities.

Conversion and Exchange Rights

The terms on which debt securities of any series may be convertible into or exchangeable for our shares of common stock or other securities or property will be described in the applicable prospectus supplement. These terms will include:

the conversion or exchange price, or the manner of calculating the price;
the exchange or conversion period;
whether the conversion or exchange is mandatory, or voluntary at the option of the holder or at our option;
any restrictions on conversion or exchange in the event of redemption of the debt securities and any restrictions on conversion or exchange; and
the means of calculating the number of shares of our shares of common stock or other securities or property of us to be received by the holders of debt securities.

The conversion or exchange price of any debt securities of any series that are convertible into our shares of common stock, may be adjusted for any stock dividends, stock splits, reclassification, combinations or similar transactions, as set forth in the applicable prospectus supplement (Article Sixteen).

Governing Law

The indentures will be governed by the laws of the State of New York.

Redemption of Debt Securities

The debt securities may be subject to optional or mandatory redemption on terms and conditions described in the applicable prospectus supplement. Subject to such terms, we may opt at any time to partially or entirely redeem the debt securities.

From and after notice has been given as provided in the applicable indenture, if funds for the redemption of any debt securities called for redemption shall have been made available on the redemption date, the debt securities will cease to bear interest on the date fixed for the redemption specified in the notice, and the only right of the holders of the debt securities will be to receive payment of the redemption price.

24

DESCRIPTION OF WARRANTS

We may issue and offer warrants under the material terms and conditions described in this prospectus and any accompanying prospectus supplement. The accompanying prospectus supplement may add, update or change the terms and conditions of the warrants as described in this prospectus.

We may issue warrants to purchase shares of common stock, preferred stock and/or debt securities in one or more series. Warrants may be issued independently or together with any other securities and may be attached to, or separate from, such securities. Each series of warrants will be issued under a separate warrant agreement to be entered into between us and a warrant agent. The warrant agent will act solely as our agent and will not assume any obligation or relationship of agency for or with holders or beneficial owners of warrants. The terms of any warrants to be issued and a description of the material provisions of the applicable warrant agreement will be set forth in the applicable prospectus supplement.

The applicable prospectus supplement will describe the following terms of any warrants in respect of which this prospectus is being delivered:

the title of such warrants;
the aggregate number of such warrants;
the price or prices at which such warrants will be issued and exercised;
the currency or currencies in which the price of such warrants will be payable;
the securities purchasable upon exercise of such warrants;
the date on which the right to exercise such warrants shall commence and the date on which such right shall expire;
if applicable, the minimum or maximum amount of such warrants which may be exercised at any one time;
if applicable, the designation and terms of the securities with which such warrants are issued and the number of such warrants issued with each such security;
if applicable, the date on and after which such warrants and the related securities will be separately transferable;
information with respect to book-entry procedures, if any;
material Israeli and United States federal income tax consequences, if any;
the anti-dilution provisions of the warrants, if any; and
any other terms of such warrants, including terms, procedures and limitations relating to the exchange and exercise of such warrants.

The description in the applicable prospectus supplement of any warrants we offer will not necessarily be complete and will be qualified in its entirety by reference to the applicable warrant agreement and warrant certificate, which will be filed with the SEC if we offer warrants. For more information on how you can obtain copies of the applicable warrant agreement and warrant certificate if we offer warrants, see "Where You Can Find More Information" and "Incorporation of Certain Documents by Reference" beginning on page 31. We urge you to read the applicable warrant agreement and warrant certificate and any applicable prospectus supplement in their entirety.

25

DESCRIPTION OF UNITS

We may issue units comprised of one or more of the other securities that may be offered under this prospectus, in any combination. Each unit will be issued so that the holder of the unit is also the holder of each security included in the unit. Thus, the holder of a unit will have the rights and obligations of a holder of each included security. The unit agreement under which a unit is issued may provide that the securities included in the unit may not be held or transferred separately at any time, or at any time before a specified date.

The prospectus supplement relating to any units we offer will, to the extent applicable, include specific terms relating to the offering, including some or all of the following:

the material terms of the units and of the securities comprising the units, including whether and under what circumstances those securities may be held or transferred separately;
any material provisions relating to the issuance, payment, settlement, transfer or exchange of the units or of the securities comprising the units; and
any material provisions of the governing unit agreement that differ from those described above.

The description in the applicable prospectus supplement of any units we offer will not necessarily be complete and will be qualified in its entirety by reference to the applicable unit agreement, which will be filed with the SEC if we offer units. For more information on how you can obtain copies of the applicable unit agreement if we offer units, see "Where You Can Find More Information" and "Incorporation of Certain Documents by Reference" beginning on page 31. We urge you to read the applicable unit agreement and any applicable prospectus supplement in their entirety.

26

FORMS OF SECURITIES

Each debt security and, to the extent applicable, warrant, subscription right and unit, will be represented either by a certificate issued in definitive form to a particular investor or by one or more global securities representing the entire issuance of securities. Certificated securities in definitive form and global securities will be issued in registered form. Definitive securities name you or your nominee as the owner of the security, and in order to transfer or exchange these securities or to receive payments other than interest or other interim payments, you or your nominee must physically deliver the securities to the trustee, registrar, paying agent or other agent, as applicable. Global securities name a depositary or its nominee as the owner of the debt securities or warrants represented by these global securities. The depositary maintains a computerized system that will reflect each investor's beneficial ownership of the securities through an account maintained by the investor with its broker/dealer, bank, trust company or other representative, as we explain more fully below.

Global Securities

Registered Global Securities. We may issue the registered debt securities and, to the extent applicable, warrants, subscription rights and units, in the form of one or more fully registered global securities that will be deposited with a depositary or its nominee identified in the applicable prospectus supplement and registered in the name of that depositary or nominee. In those cases, one or more registered global securities will be issued in a denomination or aggregate denominations equal to the portion of the aggregate principal or face amount of the securities to be represented by registered global securities. Unless and until it is exchanged in whole for securities in definitive registered form, a registered global security may not be transferred except as a whole by and among the depositary for the registered global security, the nominees of the depositary or any successors of the depositary or those nominees.

If not described below, any specific terms of the depositary arrangement with respect to any securities to be represented by a registered global security will be described in the prospectus supplement relating to those securities. We anticipate that the following provisions will apply to all depositary arrangements.

Ownership of beneficial interests in a registered global security will be limited to persons, called participants, that have accounts with the depositary or persons that may hold interests through participants. Upon the issuance of a registered global security, the depositary will credit, on its book-entry registration and transfer system, the participants' accounts with the respective principal or face amounts of the securities beneficially owned by the participants. Any dealers, underwriters or agents participating in the distribution of the securities will designate the accounts to be credited. Ownership of beneficial interests in a registered global security will be shown on, and the transfer of ownership interests will be effected only through, records maintained by the depositary, with respect to interests of participants, and on the records of participants, with respect to interests of persons holding through participants. The laws of some states may require that some purchasers of securities take physical delivery of these securities in definitive form. These laws may impair your ability to own, transfer or pledge beneficial interests in registered global securities.

So long as the depositary, or its nominee, is the registered owner of a registered global security, that depositary or its nominee, as the case may be, will be considered the sole owner or holder of the securities represented by the registered global security for all purposes under the applicable indenture or warrant agreement. Except as described below, owners of beneficial interests in a registered global security will not be entitled to have the securities represented by the registered global security registered in their names, will not receive or be entitled to receive physical delivery of the securities in definitive form and will not be considered the owners or holders of the securities under the applicable indenture or warrant agreement. Accordingly, each person owning a beneficial interest in a registered global security must rely on the procedures of the depositary for that registered global security and, if that person is not a participant, on the procedures of the participant through which the person owns its interest, to exercise any rights of a holder under the applicable indenture or warrant agreement. We understand that under existing industry practices, if we request any action of holders or if an owner of a beneficial interest in a registered global security desires to give or take any action that a holder is entitled to give or take under the applicable indenture or warrant agreement, the depositary for the registered global security would authorize the participants holding the relevant beneficial interests to give or take that action, and the participants would authorize beneficial owners owning through them to give or take that action or would otherwise act upon the instructions of beneficial owners holding through them.

Principal, premium, if any, interest payments on debt securities and any payments to holders with respect to warrants represented by a registered global security registered in the name of a depositary or its nominee will be made to the depositary or its nominee, as the case may be, as the registered owner of the registered global security. None of the Company, the trustees, the warrant agents or any other agent of the Company, the trustees or the warrant agents will have any responsibility or liability for any aspect of the records relating to payments made on account of beneficial ownership interests in the registered global security or for maintaining, supervising or reviewing any records relating to those beneficial ownership interests.

We expect that the depositary for any of the securities represented by a registered global security, upon receipt of any payment of principal, premium, interest or other distribution of underlying securities or other property to holders on that registered global security, will immediately credit participants' accounts in amounts proportionate to their respective beneficial interests in that registered global security as shown on the records of the depositary. We also expect that payments by participants to owners of beneficial interests in a registered global security held through participants will be governed by standing customer instructions and customary practices, as is now the case with the securities held for the accounts of customers in bearer form or registered in "street name," and will be the responsibility of those participants.

If the depositary for any of these securities represented by a registered global security is at any time unwilling or unable to continue as depositary or ceases to be a clearing agency registered under the Exchange Act, and a successor depositary registered as a clearing agency under the Exchange Act is not appointed by us within 90 days, we will issue securities in definitive form in exchange for the registered global security that had been held by the depositary. Any securities issued in definitive form in exchange for a registered global security will be registered in the name or names that the depositary gives to the relevant trustee or warrant agent or other relevant agent of ours or theirs. It is expected that the depositary's instructions will be based upon directions received by the depositary from participants with respect to ownership of beneficial interests in the registered global security that had been held by the depositary.

27

PLAN OF DISTRIBUTION

We may sell the securities described in this prospectus from time to time in one or more of the following ways:

through agents;
to or through one or more underwriters on a firm commitment or agency basis;
through put or call option transactions relating to the securities;
to or through dealers, who may act as agents or principals, including a block trade (which may involve crosses) in which a broker or dealer so engaged will attempt to sell as agent but may position and resell a portion of the block as principal to facilitate the transaction;
through privately negotiated transactions;
purchases by a broker or dealer as principal and resale by such broker or dealer for its own account pursuant to this prospectus;
directly to purchasers, including our affiliates, through a specific bidding or auction process, on a negotiated basis or otherwise; to or through one or more underwriters on a firm commitment or best efforts basis;
exchange distributions and/or secondary distributions;
ordinary brokerage transactions and transactions in which the broker solicits purchasers;
in an "at the market offering", within the meaning of Rule 415(a)(4) of the Securities into an existing trading market, on an exchange or otherwise;
transactions not involving market makers or established trading markets, including direct sales or privately negotiated transactions;
transactions in options, swaps or other derivatives that may or may not be listed on an exchange;
through any other method permitted pursuant to applicable law; or
through a combination of any such methods of sale.

At any time a particular offer of the securities covered by this prospectus is made, a revised prospectus or prospectus supplement, if required, will be distributed which will set forth the aggregate amount of securities covered by this prospectus being offered and the terms of the offering, including the name or names of any underwriters, dealers, brokers or agents, any discounts, commissions, concessions and other items constituting compensation from us and any discounts, commissions or concessions allowed or re-allowed or paid to dealers. Such prospectus supplement, and, if necessary, a post-effective amendment to the registration statement of which this prospectus is a part, will be filed with the SEC to reflect the disclosure of additional information with respect to the distribution of the securities covered by this prospectus. In order to comply with the securities laws of certain states, if applicable, the securities sold under this prospectus may only be sold through registered or licensed broker-dealers. In addition, in some states the securities may not be sold unless they have been registered or qualified for sale in the applicable state or an exemption from registration or qualification requirements is available and is complied with.

The distribution of securities may be effected from time to time in one or more transactions, including block transactions and transactions on the Nasdaq Capital Market or any other organized market where the securities may be traded. The securities may be sold at a fixed price or prices, which may be changed, or at market prices prevailing at the time of sale, at prices relating to the prevailing market prices or at negotiated prices. The consideration may be cash or another form negotiated by the parties. Agents, underwriters or broker-dealers may be paid compensation for offering and selling the securities. That compensation may be in the form of discounts, concessions or commissions to be received from us or from the purchasers of the securities. Any dealers and agents participating in the distribution of the securities may be deemed to be underwriters, and compensation received by them on resale of the securities may be deemed to be underwriting discounts. If any such dealers or agents were deemed to be underwriters, they may be subject to statutory liabilities under the Securities Act.

28

Agents may from time to time solicit offers to purchase the securities. If required, we will name in the applicable prospectus supplement any agent involved in the offer or sale of the securities and set forth any compensation payable to the agent. Unless otherwise indicated in the prospectus supplement, any agent will be acting on a best efforts basis for the period of its appointment. Any agent selling the securities covered by this prospectus may be deemed to be an underwriter, as that term is defined in the Securities Act, of the securities.

To the extent that we make sales to or through one or more underwriters or agents in at-the-market offerings, we will do so pursuant to the terms of a distribution agreement between us and the underwriters or agents. If we engage in at-the-market sales pursuant to a distribution agreement, we will sell any of our listed securities to or through one or more underwriters or agents, which may act on an agency basis or on a principal basis. During the term of any such agreement, we may sell any of our listed securities on a daily basis in exchange transactions or otherwise as we agree with the underwriters or agents. The distribution agreement will provide that any of our listed securities which are sold will be sold at prices related to the then prevailing market prices for our listed securities. Therefore, exact figures regarding proceeds that will be raised or commissions to be paid cannot be determined at this time and will be described in a prospectus supplement. Pursuant to the terms of the distribution agreement, we also may agree to sell, and the relevant underwriters or agents may agree to solicit offers to purchase, blocks of our listed securities. The terms of each such distribution agreement will be set forth in more detail in a prospectus supplement to this prospectus.

If underwriters are used in a sale, securities will be acquired by the underwriters for their own account and may be resold from time to time in one or more transactions, including negotiated transactions, at a fixed public offering price or at varying prices determined at the time of sale, or under delayed delivery contracts or other contractual commitments. Securities may be offered to the public either through underwriting syndicates represented by one or more managing underwriters or directly by one or more firms acting as underwriters. If an underwriter or underwriters are used in the sale of securities, an underwriting agreement will be executed with the underwriter or underwriters, as well as any other underwriter or underwriters, with respect to a particular underwritten offering of securities, and will set forth the terms of the transactions, including compensation of the underwriters and dealers and the public offering price, if applicable. The prospectus and prospectus supplement will be used by the underwriters to resell the securities.

If a dealer is used in the sale of the securities, we or an underwriter will sell the securities to the dealer, as principal. The dealer may then resell the securities to the public at varying prices to be determined by the dealer at the time of resale. To the extent required, we will set forth in the prospectus supplement the name of the dealer and the terms of the transactions.

We may directly solicit offers to purchase the securities and may make sales of securities directly to institutional investors or others. These persons may be deemed to be underwriters within the meaning of the Securities Act with respect to any resale of the securities. To the extent required, the prospectus supplement will describe the terms of any such sales, including the terms of any bidding or auction process, if used.

Agents, underwriters and dealers may be entitled under agreements which may be entered into with us to indemnification by us against specified liabilities, including liabilities incurred under the Securities Act, or to contribution by us to payments they may be required to make in respect of such liabilities. If required, the prospectus supplement will describe the terms and conditions of the indemnification or contribution. Some of the agents, underwriters or dealers, or their affiliates may be customers of, engage in transactions with or perform services for us or our subsidiaries.

Any person participating in the distribution of securities registered under the registration statement that includes this prospectus will be subject to applicable provisions of the Exchange Act, and the applicable SEC rules and regulations, including, among others, Regulation M, which may limit the timing of purchases and sales of any of our securities by that person. Furthermore, Regulation M may restrict the ability of any person engaged in the distribution of our securities to engage in market-making activities with respect to our securities. These restrictions may affect the marketability of our securities and the ability of any person or entity to engage in market-making activities with respect to our securities.

Certain persons participating in an offering may engage in over-allotment, stabilizing transactions, short-covering transactions, penalty bids and other transactions that stabilize, maintain or otherwise affect the price of the offered securities. These activities may maintain the price of the offered securities at levels above those that might otherwise prevail in the open market, including by entering stabilizing bids, effecting syndicate covering transactions or imposing penalty bids, each of which is described below:

a stabilizing bid means the placing of any bid, or the effecting of any purchase, for the purpose of pegging, fixing or maintaining the price of a security.
a syndicate covering transaction means the placing of any bid on behalf of the underwriting syndicate or the effecting of any purchase to reduce a short position created in connection with the offering.
29
a penalty bid means an arrangement that permits the managing underwriter to reclaim a selling concession from a syndicate member in connection with the offering when offered securities originally sold by the syndicate member are purchased in syndicate covering transactions.

These transactions may be effected on an exchange or automated quotation system, if the securities are listed on that exchange or admitted for trading on that automated quotation system, or in the over-the-counter market or otherwise.

If so indicated in the applicable prospectus supplement, we will authorize agents, underwriters or dealers to solicit offers from certain types of institutions to purchase offered securities from us at the public offering price set forth in such prospectus supplement pursuant to delayed delivery contracts providing for payment and delivery on a specified date in the future. Such contracts will be subject only to those conditions set forth in the prospectus supplement and the prospectus supplement will set forth the commission payable for solicitation of such contracts.

In addition, shares of common stock, preferred stock or warrants may be issued upon conversion of or in exchange for debt securities or other securities.

Any underwriters to whom offered securities are sold for public offering and sale may make a market in such offered securities, but such underwriters will not be obligated to do so and may discontinue any market making at any time without notice. The offered securities may or may not be listed on a national securities exchange. No assurance can be given that there will be a market for the offered securities.

Any securities that qualify for sale pursuant to Rule 144 or Regulation S under the Securities Act may be sold under Rule 144 or Regulation S rather than pursuant to this prospectus.

In connection with offerings made through underwriters or agents, we may enter into agreements with such underwriters or agents pursuant to which we receive our outstanding securities in consideration for the securities being offered to the public for cash. In connection with these arrangements, the underwriters or agents may also sell securities covered by this prospectus to hedge their positions in these outstanding securities, including in short sale transactions. If so, the underwriters or agents may use the securities received from us under these arrangements to close out any related open borrowings of securities.

We may enter into derivative transactions with third parties or sell securities not covered by this prospectus to third parties in privately negotiated transactions. If the applicable prospectus supplement indicates, in connection with those derivatives, such third parties (or affiliates of such third parties) may sell securities covered by this prospectus and the applicable prospectus supplement, including in short sale transactions. If so, such third parties (or affiliates of such third parties) may use securities pledged by us or borrowed from us or others to settle those sales or to close out any related open borrowings of shares, and may use securities received from us in settlement of those derivatives to close out any related open borrowings of shares. The third parties (or affiliates of such third parties) in such sale transactions will be underwriters and will be identified in the applicable prospectus supplement (or a post-effective amendment).

We may loan or pledge securities to a financial institution or other third party that in turn may sell the securities using this prospectus. Such financial institution or third party may transfer its short position to investors in our securities or in connection with a simultaneous offering of other securities offered by this prospectus or in connection with a simultaneous offering of other securities offered by this prospectus.

30

LEGAL MATTERS

The validity of the issuance of the securities offered hereby will be passed upon for us by McDermott Will & Emery LLP, New York, New York. Additional legal matters may be passed upon for us or any underwriters, dealers or agents, by counsel that we will name in the applicable prospectus supplement.

EXPERTS

Our financial statements as of December 31, 2021 and 2020, and for each of the years then ended, have been incorporated by reference herein in reliance upon the report of Haskell & White LLP, independent registered public accounting firm, and upon the authority of said firm as experts in accounting and auditing.

WHERE YOU CAN FIND MORE INFORMATION

This prospectus constitutes a part of a registration statement on Form S-3 filed under the Securities Act. As permitted by the SEC's rules, this prospectus and any prospectus supplement, which form a part of the registration statement, do not contain all the information that is included in the registration statement. You will find additional information about us in the registration statement. Any statements made in this prospectus or any prospectus supplement concerning legal documents are not necessarily complete and you should read the documents that are filed as exhibits to the registration statement or otherwise filed with the SEC for a more complete understanding of the document or matter.

We are subject to the informational requirements of the Exchange Act, and, in accordance with those requirements, file annual, quarterly and current reports, proxy statements and other information with the SEC. Such reports, proxy statements and other information, as well as this registration statement and the exhibits and schedules thereto, are available on the SEC website at www.sec.gov. Copies of these documents may also be accessed on our website at www.indaptusrx.com. Our internet website and the information contained therein or connected thereto are not incorporated into this prospectus or any amendment or supplement thereto.

INCORPORATION OF CERTAIN DOCUMENTS BY REFERENCE

The SEC allows us to "incorporate by reference" information that we file with it into this prospectus, which means that we can disclose important information to you by referring you to those documents. The information incorporated by reference is deemed to be part of this prospectus, and subsequent information that we file with the SEC will automatically update and supersede that information. Any statement contained in this prospectus or a previously filed document incorporated by reference will be deemed to be modified or superseded for purposes of this prospectus to the extent that a statement contained in this prospectus or a subsequently filed document incorporated by reference modifies or replaces that statement.

This prospectus and any accompanying prospectus supplement incorporate by reference the documents set forth below that have previously been filed with the SEC:

our Annual Report on Form 10-K for the fiscal year ended on December 31, 2021, filed with the SEC on March 21, 2022;

our Quarterly Report on Form 10-Q for the quarter ended on March 31, 2022, filed with the SEC on May 12, 2022;
our Quarterly Report on Form 10-Q for the quarter ended on June 30, 2022, filed with the SEC on August 8, 2022;

our Current Reports on Form 8-K (other than the information furnished pursuant to Item 2.02 or 7.01 thereof or related exhibits furnished pursuant to Item 9.01 thereof) filed with the SEC on January 3, 2022, February 1, 2022, May 19, 2022, June 1, 2022 and July 21, 2022; and

the description of our shares of common stock contained in our Registration Statement on Form 8-A (File No. 001-40652), filed with the SEC on July 23, 2021, including any amendment or report filed for the purpose of updating such description.

All reports and other documents we subsequently file pursuant to Section 13(a), 13(c), 14 or 15(d) of the Exchange Act in this prospectus, prior to the termination of this offering, including all such documents we may file with the SEC after the date of the initial registration statement of which this prospectus is a part and prior to the effectiveness of the registration statement, but excluding any information furnished to, rather than filed with, the SEC, will also be incorporated by reference into this prospectus and deemed to be part of this prospectus from the date of the filing of such reports and documents.

We will provide you without charge, upon your written or oral request, a copy of any of the documents incorporated by reference in this prospectus, other than exhibits to such documents which are not specifically incorporated by reference into such documents. You may request a copy of any or all of these filings, at no cost, by writing or telephoning us at: Nir Sassi, Chief Financial Officer, 3 Columbus Circle, 15th Floor, New York, NY 10019. You may also access the documents incorporated by reference in this prospectus through our website at www.indaputus.com. Except for the specific incorporated documents listed above, no information available on or through our website shall be deemed to be incorporated in this prospectus or the registration statement of which it forms a part.

31

1,643,837 Shares of Common Stock

Prospectus Supplement

Paulson Investment Company, LLC

August 7, 2024