Curis Inc.

10/30/2024 | Press release | Distributed by Public on 10/30/2024 04:28

Supplemental Prospectus - Form 424B5

Document

Filed pursuant to Rule 424(b)(5)
Registration No. 333-276950

PROSPECTUS SUPPLEMENT
(to Prospectus dated April 12, 2024)
2,398,414 Shares


COMMON STOCK


We are offering 2,398,414 shares of our common stock to investors pursuant to this prospectus supplement and the accompanying prospectus and a securities purchase agreement with each investor.

In a concurrent private placement, or the Warrant Private Placement, we are also selling to the investors common stock warrants, or the Unregistered Warrants, to purchase up to an aggregate of 2,398,414 shares, or the Unregistered Warrant Shares, of our common stock. The Unregistered Warrants and Unregistered Warrant Shares, which we refer to collectively as the Unregistered Securities, are not being registered under the Securities Act of 1933, as amended, or the Securities Act, and are not offered pursuant to this prospectus supplement and the accompanying prospectus. The Unregistered Securities are being offered pursuant to an exemption from the registration requirements of the Securities Act provided in Section 4(a)(2) of the Securities Act and/or Regulation D promulgated thereunder. The Unregistered Warrants are exercisable immediately and exercisable for five years from the date of issuance and have an exercise price of $4.92per Unregistered Warrant Share.

Our common stock is listed on The Nasdaq Capital Market under the symbol "CRIS." The last reported sale price of our common stock on October 28, 2024, was $4.92 per share.

We are a "smaller reporting company" as defined under the federal securities laws and, as such, have elected to comply with certain reduced public company reporting requirements.

Investing in our common stock involves a high degree of risk. Please read the "Risk Factors" beginning on Page S-10 of this prospectus supplement and found in the documents incorporated by reference in this prospectus supplement.
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 the accompanying prospectus is truthful or complete. Any representation to the contrary is a criminal offense.

We have engaged Truist Securities, Inc. and Laidlaw & Company (UK) Ltd., which we refer to as the placement agents, as our placement agents in connection with this offering. The placement agents have no obligation to buy any of the securities from us or to arrange for the purchase or sale of any specific number or dollar amount of securities. We have agreed to pay the placement agents the placement agent fees set forth in the table below. There is no arrangement for funds to be received in escrow, trust or similar arrangement. There is no minimum offering requirement. We will bear all costs associated with the offering. See "Plan of Distribution" beginning on page S-15 of this prospectus supplement for more information regarding these arrangements.


Per Share
Total
Offering price
$5.045
$12,099,999
Placement agent fees(1)
$0.389
$934,000
Proceeds, before expenses, to us(2)
$4.656
$11,165,999

(1) In addition, we have agreed to reimburse the placement agents for certain out-of-pocket expenses. See "Plan of Distribution" beginning on page S-15 of this prospectus supplement for additional information with respect to the compensation we will pay the placement agents in connection with this offering.
(2) The amount of the offering proceeds to us presented in this table does not take into account any proceeds from the exercise of any of the Unregistered Warrants being issued in the Warrant Private Placement.

Delivery of the securities offered hereby is expected to occur on or about October 30, 2024, subject to the satisfaction of certain closing conditions.

TRUIST SECURITIES LAIDLAW & COMPANY (UK) LTD.
The date of this prospectus supplement is October 28, 2024






TABLE OF CONTENTS

ABOUT THIS PROSPECTUS SUPPLEMENT
S-4
CAUTIONARY NOTE REGARDING FORWARD-LOOKING STATEMENTS AND INDUSTRY DATA
S-5
WHERE YOU CAN FIND MORE INFORMATION
S-6
INCORPORATION BY REFERENCE
S-6
SUMMARY
S-7
THE OFFERING
S-9
RISK FACTORS
S-10
USE OF PROCEEDS
S-11
DILUTION
S-12
DESCRIPTION OF COMMON STOCK
S-13
WARRANT PRIVATE PLACEMENT
S-14
PLAN OF DISTRIBUTION
S-15
MATERIAL U.S. FEDERAL TAX CONSIDERATIONS FOR NON-U.S. HOLDERS OF COMMON STOCK
S-17
LEGAL MATTERS
S-20
EXPERTS
S-20



Prospectus
ABOUT THIS PROSPECTUS SUPPLEMENT
2
WHERE YOU CAN FIND MORE INFORMATION
3
INCORPORATION BY REFERENCE
3
CAUTIONARY NOTE REGARDING FORWARD-LOOKING STATEMENTS AND INDUSTRY DATA
4
CURIS, INC.
6
RISK FACTORS
7
USE OF PROCEEDS
8
DESCRIPTION OF COMMON STOCK
9
PLAN OF DISTRIBUTION
12
LEGAL MATTERS
14
EXPERTS
14
















ABOUT THIS PROSPECTUS SUPPLEMENT

This prospectus supplement and the accompanying prospectus form part of a registration statement on Form S-3 that we filed with the Securities and Exchange Commission, or SEC, utilizing a "shelf" registration process. This document is in two parts. The first part is this prospectus supplement, which describes the specific terms of this offering and also adds to and updates information contained in the accompanying prospectus and the documents incorporated by reference herein or therein. The second part, the accompanying prospectus, provides more general information. Generally, when we refer to this prospectus, we are referring to both parts of this document combined. To the extent there is a conflict between the information contained in this prospectus supplement and the information contained in the accompanying prospectus or any document incorporated by reference herein or therein filed prior to the date of this prospectus supplement, you should rely on the information in this 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 in the accompanying prospectus-the statement in the document having the later date modifies or supersedes the earlier statement.

We further note that the representations, warranties and covenants made by us in any agreement that is filed as an exhibit to any document that is incorporated by reference herein or in the accompanying prospectus were made solely for the benefit of the parties to such agreement, including, in some cases, for the purpose of allocating risk among the parties to such agreement, and should not be deemed to be a representation, warranty or covenant to you. Moreover, such representations, warranties or covenants were accurate only as of the date when made. Accordingly, such representations, warranties and covenants should not be relied on as accurately representing the current state of our affairs.

You should rely only on the information contained in or incorporated by reference in this prospectus supplement, the accompanying prospectus and in any free writing prospectus we have authorized for use in connection with this offering. We have not, and the placement agents have not, authorized anyone to provide any information other than that contained or incorporated by reference in this prospectus supplement, in the accompanying prospectus or in any free writing prospectus prepared by or on behalf of us or to which we have referred you. We and the placement agents take no responsibility for, and can provide no assurance as to the reliability of, any other information that others may give you.

We are not, and the placement agents are not, making an offer to sell, or a solicitation of an offer to purchase, the securities offered by this prospectus supplement and the accompanying prospectus in any jurisdiction or to or from any person to whom or from whom it would be unlawful to make such offer or solicitation of an offer in such jurisdiction. You should assume that the information appearing in this prospectus supplement, the accompanying prospectus, the documents incorporated by reference in this prospectus supplement and the accompanying prospectus, and in any free writing prospectus prepared by or on behalf of us that we have authorized for use in connection with this offering is accurate only as of the dates of those respective documents. Our business, financial condition, results of operations and prospects may have changed since those dates. You should read this prospectus supplement, the accompanying prospectus, the documents incorporated by reference in this prospectus supplement and the accompanying prospectus, and any free writing prospectus prepared by or on behalf of us that we have authorized for use in connection with this offering, in their entirety before making an investment decision. You should also read and consider the information in the documents we have referred you to in the sections of this prospectus supplement and the accompanying prospectus entitled "Where You Can Find More Information" and "Incorporation by Reference."

Other than in the United States, no action has been taken by us or the placement agents that would permit a public offering of the securities offered by this prospectus supplement and the accompanying prospectus in any jurisdiction where action for that purpose is required. The securities offered by this prospectus supplement and the accompanying prospectus may not be offered or sold, directly or indirectly, nor may this prospectus supplement, the accompanying prospectus or any other offering material or advertisements in connection with the offer and sale of any such securities be distributed or published in any jurisdiction, except under circumstances that will result in compliance with the applicable rules and regulations of that jurisdiction. Persons into whose possession this prospectus supplement and the accompanying prospectus come are advised to inform themselves about and to observe any restrictions relating to the offering of the securities and the distribution of this prospectus supplement and the accompanying prospectus. This prospectus supplement and the accompanying prospectus do not constitute, and may not be used in connection with, an offer to sell or a solicitation of an offer to purchase any securities offered by this prospectus supplement and the accompanying prospectus in any jurisdiction in which such an offer or a solicitation would be unlawful.

Unless the context requires otherwise, all references in this prospectus supplement and the accompanying prospectus to "we," "us," "our," "Curis," the "Company" and similar designations refer to Curis, Inc. and its subsidiaries. The Curis logo is a trademark of Curis in the United States and in other select countries. We may indicate U.S. trademark registrations and U.S. trademarks with the symbols "®" and "™", respectively. Other third-party logos and product/trade names are registered trademarks or trade names of their respective owners.















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CAUTIONARY NOTE REGARDING FORWARD-LOOKING STATEMENTS AND INDUSTRY DATA

This prospectus supplement, the accompanying prospectus and the documents we incorporate by reference herein and therein include forward-looking statements within the meaning of Section 27A of the Securities Act and Section 21E of the Securities Exchange Act of 1934, as amended, which we refer to as the Exchange Act. For purposes of these statutes, any statement contained in this prospectus supplement, the accompanying prospectus or in the documents we incorporate by reference herein and therein other than a statement of historical fact, may be a forward-looking statement, including statements regarding our strategy, future operations, future financial position, future revenue, projected costs, prospects, plans and objectives of management. In some cases, you can identify forward-looking statements by such terms as "anticipate," "believe," "could," "estimate," "expect," "focus," "intend," "may," "plan," "potential," "project," "seek," "should," "strategy," "will," "would" or other words that convey uncertainty of future events or outcomes to identify these forward-looking statements. Forward-looking statements may include, but are not limited to, statements about:

•the initiation, timing, progress and results of future preclinical studies and clinical trials, and our research and development program for emavusertib;
•our estimates of the period in which we anticipate that existing cash and cash equivalents and the proceeds of this offering will enable us to fund our current and planned operations;
•our ability to continue as a going concern;
•our ability to obtain additional financing;
•our expectations related to the use of proceeds from this offering;
•our ability to establish and maintain collaborations;
•our plans to develop and commercialize emavusertib;
•the timing or likelihood of regulatory filings and approvals;
•the implementation of our business model and strategic plans for our business, drug candidate and technology;
•our estimates regarding expenses, future revenue and capital requirements;
•developments and projections relating to our competitors and our industry;
•our commercialization, marketing and manufacturing capabilities and strategy;
•the rate and degree of market acceptance and clinical utility of our products;
•our competitive position; and
•our intellectual property position.

Our actual results may differ materially from those indicated by these forward-looking statements as a result of various important factors, including the factors referred to under the heading "Risk Factors" beginning on page S-10 of this prospectus supplement and in the "Risk Factors" sections of our Annual Report on Form 10-K for the fiscal year ended December 31, 2023. If one or more of these factors materialize, or if any underlying assumptions prove incorrect, our actual results, performance or achievements may vary materially from any future results, performance or achievements expressed or implied by these forward-looking statements.

You should consider these factors and the other cautionary statements made in this prospectus supplement, the accompanying prospectus and the documents we incorporate by reference herein and therein as being applicable to all related forward-looking statements wherever they appear in this prospectus supplement, the accompanying prospectus, or the documents incorporated by reference. While we may elect to update forward-looking statements wherever they appear in this prospectus supplement, the accompanying prospectus, or the documents incorporated by reference herein and therein, we do not assume, and specifically disclaim, any obligation to do so, whether as a result of new information, future events or otherwise, except as required by law.

This prospectus supplement, the accompanying prospectus and the documents incorporated by reference herein and therein include statistical and other industry and market data that we obtained from industry publications and research, surveys, and studies conducted by third parties as well as our own estimates. All of the market data used in this prospectus supplement, the accompanying prospectus and the documents incorporated by reference herein and therein involve a number of assumptions and limitations, and you are cautioned not to give undue weight to such data. Industry publications and third-party research, surveys, and studies generally indicate that their information has been obtained from sources believed to be reliable, although they do not guarantee the accuracy or completeness of such information. Our estimates of the potential market opportunities for our product candidates include several key assumptions based on our industry knowledge, industry publications, third-party research, and other surveys, which may be based on a small sample size and may fail to accurately reflect market opportunities. While we believe that our internal assumptions are reasonable, no independent source has verified such assumptions.



S-5

WHERE YOU CAN FIND MORE INFORMATION

We file annual, quarterly and current reports, proxy statements and other information with the SEC. Our SEC filings are available to the public over the Internet at the SEC's website at http://www.sec.gov. Copies of certain information filed by us with the SEC are also available on our website at http://www.curis.com. Our website is not a part of this prospectus supplement or the accompanying prospectus and is not incorporated by reference in this prospectus supplement or the accompanying prospectus.

This prospectus supplement is part of a registration statement we filed with the SEC. This prospectus supplement and the accompanying prospectus omit some information contained in the registration statement in accordance with SEC rules and regulations. You should review the information and exhibits in the registration statement for further information on us and our consolidated subsidiaries and the securities we are offering. Statements in this prospectus supplement and the accompanying prospectus concerning any document we filed as an exhibit to the registration statement or that we otherwise filed with the SEC are not intended to be comprehensive and are qualified by reference to these filings. You should review the complete document to evaluate these statements. You can obtain a copy of the registration statement from the SEC's website.


INCORPORATION BY REFERENCE

The SEC allows us to incorporate into this prospectus supplement and the accompanying prospectus information that we file with the SEC in other documents. This means that we can disclose important information to you by referring to other documents that contain that information. Any information that we incorporate by reference is considered part of this prospectus supplement and the accompanying prospectus, except in each case for information contained in any such filing where we indicate that such information is being furnished or is not to be considered "filed" under the Exchange Act.
Statements contained in documents that we file with the SEC and that are incorporated by reference in this prospectus supplement and the accompanying prospectus will automatically update and supersede information contained in this prospectus supplement and the accompanying prospectus, including information in previously filed documents or reports that have been incorporated by reference in this prospectus supplement and the accompanying prospectus, to the extent the new information differs from or is inconsistent with the old information. This means that you must look at all of the SEC filings that we incorporate by reference to determine if any of the statements in this prospectus supplement, the accompanying prospectus or in any document previously incorporated by reference have been modified or superseded.

We incorporate by reference the documents and other information listed or referred to below (File No. 000-30347) and any future filings we make with the SEC under Sections 13(a), 13(c), 14 or 15(d) of the Exchange Act (in each case, other than those documents or the portions of those documents not deemed to be filed) until all of the securities which this prospectus supplement relates have been sold or the offering is otherwise terminated:
• Annual Report on Form 10-Kfor the fiscal year ended December 31, 2023, filed on February 8, 2024;
• Quarterly Reports on Form 10-Qfor the quarters ended March 31, 2024 and June 30, 2024, filed on May 7, 2024 and August 1, 2024, respectively;
• The information specifically incorporated by reference into our Annual Report on Form 10-Kfor the fiscal year ended December 31, 2023 from our Definitive Proxy Statement on Schedule 14A, filed on April 10, 2024;
• Current Reports on Form 8-K filed on May 14, 2024(except Item 7.01 and Item 9.01) and May 23, 2024; and
• The description of our common stock contained in our Registration Statement on Form 8-Afiled on April 13, 2000, as the description therein has been updated and superseded by the description of our capital stock contained in Exhibit 4.2to our Annual Report on Form 10-K for the year ended December 31, 2023, and including any amendments and reports filed for the purpose of updating such description.

You may request a copy of these filings, at no cost, by writing or telephoning us at the following address or phone number:

Curis, Inc.
128 Spring Street Building C - Suite 500
Lexington, Massachusetts 02421
Attn: General Counsel
(617) 503-6500

S-6


SUMMARY

This summary highlights information contained elsewhere in this prospectus supplement and the accompanying prospectus and in the documents we incorporate by reference herein and therein. This summary does not contain all of the information that you should consider before deciding to invest in our securities. For a more complete understanding of our Company and this offering, you should carefully read this entire prospectus supplement and the accompanying prospectus, including the information incorporated by reference into this prospectus supplement and the accompanying prospectus, and any free writing prospectus that we have authorized for use in connection with this offering, including the "Risk Factors" section beginning on page S-10 of this prospectus supplement and the "Risk Factors" sections of our Annual Report on Form 10-K for the fiscal year ended December 31, 2023, our financial statements and the related notes and the other documents incorporated by reference in this prospectus supplement and the accompanying prospectus.

Company Overview

Emavusertib

We are a biotechnology company focused on the development of emavusertib (CA-4948), an orally available, small molecule inhibitor of Interleukin-1 receptor associated kinase, or IRAK4. IRAK4 plays an essential role in the toll-like receptor, or TLR, and interleukin-1 receptor, or IL-1R, signaling pathways, which are frequently dysregulated in patients with cancer. TLRs and the IL-1R family signal through the adaptor protein Myeloid Differentiation Primary Response Protein 88, which results in the assembly and activation of IRAK4, initiating a signaling cascade that induces cytokine and survival factor expression mediated by the NF-κB protein complex. Many B cell leukemias and lymphomas are associated with constitutive activation of the NF-κB protein complex which contributes to these cancer's proliferation and survival. The B-cell receptor, or BCR, and TLR pathways drive NF-kB activation. Preclinical studies demonstrated that targeting both the BCR and TLR pathways was more synergistic than targeting either pathway alone. Similarly, preclinical studies targeting IRAKi in combination with FMS‐like tyrosine kinase 3, or FLT3, have demonstrated the ability to overcome the adaptive resistance incurred when targeting FLT3 alone. In acute myeloid leukemia, or AML, patient derived xenografts, emavustertib has shown monotherapy anti-tumor activity as well as synergy with both azacitidine and venetoclax. In the clinic, emavusertib has shown anti-tumor activity across a broad range of hematologic malignancies including monotherapy activity in AML, particularly those with a FLT3 mutation. In non-Hodgkin's lymphoma patients, particularly in primary central nervous system lymphoma, or PCNSL, emavusertib has shown anti-tumor activity in combination with a Bruton Tyrosine Kinase, or BTK, inhibitor.

In May 2024, we streamlined our operations to focus on the TakeAim Lymphoma Phase 1/2 study, portions of the TakeAim Leukemia Phase 1/2 study, our AML Triplet study, and ongoing investigator-sponsored studies in solid tumors. We intend to complete the planned enrollment in the TakeAim Leukemia Phase 1/2 study and we deprioritized other efforts resulting in an approximate 30% reduction in our workforce.

TakeAim Leukemia

Emavusertib is currently undergoing testing in a Phase 1/2 open-label, single arm expansion trial in patients with R/R AML and high-risk myelodysplastic syndromes, or hrMDS, also known as the TakeAim Leukemia Phase 1/2 study. In January and December 2022, July and December 2023, and May 2024, we presented clinical data for patients from the ongoing TakeAim Leukemia Phase 1/2 study. We expect additional data from this study in December 2024.

TakeAim Lymphoma

In addition to the TakeAim Leukemia Phase 1/2 study, we are testing emavusertib in combination with ibrutinib, a BTK inhibitor, in a Phase 1/2 open-label, single arm expansion trial in patients with relapsed or refractory, or R/R, PCNSL, also known as the TakeAim Lymphoma Phase 1/2 study. In June 2022 and December 2023, we provided preliminary clinical data for patients with various hematological malignancies in the combination portion of the ongoing TakeAim Lymphoma Phase 1/2 study. In December 2023, we provided clinical and safety data of emavusertib in combination with ibrutinib in several non-Hodgkin's lymphoma subtypes including PCNSL patients. In September 2024, we provided additional clinical data of emavusertib in combination with ibrutinib in R/R PCNSL. We expect additional data from this study in December 2024 as well as in the first quarter of 2025.

AML Triplet Study

We have initiated a Phase 1 clinical study of emavusertib as an add-on agent to the combination of azacitidine and venetoclax to assess the safety of the triplet regimen in AML, which we refer to as the AML Triplet study. The AML Triplet study is currently being conducted in Spain, Germany, and Italy. We expect initial safety data from this study in the first quarter of 2025.

Our Collaborations and License Agreements

We are party to a collaboration agreement with Genentech Inc., or Genentech, a member of the Roche Group, under which Genentech and F. Hoffmann-La Roche Ltd, or Roche, are commercializing Erivedge® (vismodegib), a first-in-class orally administered small molecule Hedgehog signaling pathway antagonist. Erivedge is approved for the treatment of advanced basal cell carcinoma.

In January 2015, we entered into an exclusive collaboration agreement with Aurigene Discovery Technologies Limited, or Aurigene, for the discovery, development and commercialization of small molecule compounds in the areas of immuno-oncology and precision oncology. We have licensed programs under the Aurigene collaboration, including emavusertib. In September 2024, we agreed that Aurigene would expand its rights to develop and commercialize CA-170 worldwide, whereas such rights had previously been limited to development and commercialization in India, Russia and Asia.CA-170 is a PD1/VISTA program that was previously licensed by the Company.

Company Information
We were organized as a Delaware corporation in February 2000. Our principal executive offices are located at 128 Spring Street, Building C - Suite 500, Lexington, Massachusetts 02421, and our telephone number is (617) 503-6500. Our website is located at www.curis.com. The information contained in, or
S-7

that can be accessed through, our website is not incorporated by reference into this prospectus supplement or the accompanying prospectus and should not be considered to be a part of this prospectus supplement or the accompanying prospectus. Our website address is included as an inactive textual reference only.

Implications of Being a Smaller Reporting Company
We are a "smaller reporting company," meaning that the market value of our stock held by non-affiliates is less than $700 million and our annual revenue was less than $100 million during our most recently completed fiscal year. We may continue to be a smaller reporting company if either (i) the market value of our stock held by non-affiliates is less than $250 million or (ii) our annual revenue was less than $100 million during the most recently completed fiscal year and the market value of our stock held by non-affiliates is less than $700 million. For so long as we remain a smaller reporting company, we are permitted and intend to rely on exemptions from certain disclosure and other requirements that are applicable to other public companies that are not smaller reporting companies.


S-8

THE OFFERING

Common stock offered by us
2,398,414 shares of common stock.
Common stock to be outstanding after this offering and the Warrant Private Placement
8,302,692 shares of common stock (excluding shares of common stock issuable upon exercise of the Unregistered Warrants).
Warrant Private Placement
In the Warrant Private Placement, we are also selling to the investors Unregistered Warrants to purchase up to 2,398,414 Unregistered Warrant Shares. The Unregistered Warrants and the Unregistered Warrant Shares are not being registered under the Securities Act and are not offered pursuant to this prospectus supplement and the accompanying prospectus and are being offered pursuant to an exemption from the registration requirements of the Securities Act provided in Section 4(a)(2) of the Securities Act and/or Regulation D promulgated thereunder. The Unregistered Warrants are exercisable immediately, will expire five years from the date of issuance and have an exercise price of $4.92 per Unregistered Warrant Share. See "Warrant Private Placement" on page S-14 of this prospectus supplement for a more complete description of the Unregistered Warrants.
Use of proceeds
We intend to use our existing cash and cash equivalents, plus the net proceeds from the sale of securities offered under this prospectus supplement on research, development, working capital and other general corporate purposes. See "Use of Proceeds" on page S-11 of this prospectus supplement for a more complete description of the intended use of proceeds from this offering.
Risk factors
Investing in our common stock involves a high degree of risk. See "Risk Factors" beginning on page S-10 of this prospectus supplement, the "Risk Factors" sections of our Annual Report on Form 10-K for the year ended December 31, 2023, incorporated by reference into this prospectus supplement, and other information included and incorporated by reference in this prospectus supplement for a discussion of factors you should carefully consider before deciding to invest in our securities.
Nasdaq Capital Market symbol
"CRIS"


The number of shares of our common stock that will be outstanding immediately after this offering as shown above is based on 5,904,278 shares outstanding as of June 30, 2024 and excludes:
• 1,226,714 shares of our common stock issuable upon the exercise of stock options outstanding as of June 30, 2024, at a weighted average exercise price of $35.23 per share;
• an aggregate of 890,670 shares of common stock reserved for future issuance under our Fifth Amended and Restated 2010 Stock Incentive Plan as of June 30, 2024;
• an aggregate of 415,324 shares of common stock reserved for future issuance under our Amended and Restated 2010 Employee Stock Purchase Plan, as amended, as of June 30, 2024; and
• 168,640 shares of our common stock issued and sold after June 30, 2024 pursuant to our "at-the-market" offering program under our amended and restated sales agreement, or sales agreement, with Cantor Fitzgerald & Co. and JonesTrading Institutional Services LLC.

Unless we specifically state otherwise, all information in this prospectus supplement assumes no exercise of outstanding stock options described above.

In addition, the discussion above does not include (i) the $98.8 million of shares of our common stock that remains available for sale through an "at-the-market" offering program under our sales agreement or (ii) any shares of our common stock issuable upon the exercise of Unregistered Warrants being issued to the investors in the Warrant Private Placement.
S-9

RISK FACTORS

An investment in our securities involves a high degree of risk. Before deciding whether to invest in our securities, you should consider carefully the risks described below and discussed in the "Risk Factors" sections of our Annual Report on Form 10-K for the fiscal year ended December 31, 2023 incorporated by reference herein, together with other information in this prospectus supplement and the accompanying prospectus, and the information and documents incorporated by reference in this prospectus supplement and the accompanying prospectus, and in any free writing prospectus that we have authorized for use in connection with this offering. If any of these risks actually occurs, our business, financial condition, results of operations or cash flow could be seriously harmed. This could cause the trading price of our securities to decline, resulting in a loss of all or part of your investment.

Risks Related to This Offering
We have broad discretion in how we use the net proceeds of this offering, and we may not use these proceeds effectively or in ways with which you agree.
Our management will have broad discretion as to the application of the net proceeds of this offering, including for any of the purposes described in the section of this prospectus supplement entitled "Use of Proceeds." You will be relying on the judgment of our management regarding the application of the proceeds of this offering. The results and effectiveness of the use of proceeds are uncertain, and we could spend the proceeds in ways that you do not agree with or that do not improve our results of operations or enhance the value of our common stock. Our failure to apply these funds effectively could have a material adverse effect on our business, delay the development of our drug candidates and cause the price of our common stock to decline.

Investors in this offering will pay a much higher price than the book value of our stock.
The offering price of our common stock is substantially higher than the net tangible book value per share of our common stock. Therefore, if you purchase shares of common stock in this offering, you will pay a price per share of common stock that substantially exceeds our net tangible book value per share after giving effect to this offering. Based on an offering price of $5.045 per share of common stock, if you purchase shares of common stock in this offering, you will experience immediate dilution of $4.90 per share, representing the difference between the offering price of the common stock and our as adjusted net tangible book value per share after giving effect to this offering. For a further description of the dilution that you will experience immediately after this offering, see "Dilution."

You may experience future dilution as a result of future equity offerings or other issuances.
We will need additional capital to fund our research and development programs and to fulfill our planned operating goals. We may seek additional capital through a combination of private and public equity offerings, debt financings, strategic partnerships and alliances and licensing arrangements, which may cause your ownership interest to be diluted. We are currently party to the sales agreement with Cantor Fitzgerald & Co. and JonesTrading Institutional Services LLC, pursuant to which, from time to time, we may offer and sell through such agents up to $100.0 million of our common stock pursuant to one or more "at the market" offerings. To date, we have sold $1.2 million of common stock pursuant to the sales agreement. In addition, we have a significant number of options to purchase shares of our common stock outstanding. If these securities are exercised, you may incur further dilution. Moreover, to the extent that we issue additional options to purchase, or securities convertible into or exchangeable for, shares of our common stock in the future and those options or other securities are exercised, converted or exchanged, stockholders may experience further dilution.

A substantial number of shares may be sold in the market following this offering, which may depress the market price for our common stock or cause it to be highly volatile.
Sales of a substantial number of shares of our common stock in the public market following this offering, or the perception that such sales could occur, could cause the market price of our common stock to decline or cause it to be highly volatile. A substantial majority of the outstanding shares of our common stock are, and all of the shares sold in this offering will be, freely tradable without restriction or further registration under the Securities Act, unless these shares are owned or purchased by "affiliates" as that term is defined in Rule 144 under the Securities Act. In addition, we have also registered the shares of common stock that we may issue under our equity incentive plans. As a result, these shares can be freely sold in the public market upon issuance, subject to restrictions under securities laws.

Because we do not anticipate paying any cash dividends on our capital stock in the foreseeable future, capital appreciation, if any, will be your sole source of gain.
We have never declared nor paid cash dividends on our common stock. We currently plan to retain all of our future earnings, if any, to finance the operation, development and growth of our business. In addition, the terms of any future debt or credit agreements may preclude us from paying dividends. As a result, capital appreciation, if any, of our common stock will be your sole source of gain for the foreseeable future.

S-10

USE OF PROCEEDS

We estimate that the net proceeds we will receive from this offering will be approximately $10.9 million, after deducting the estimated placement agent fees and estimated offering expenses payable by us. This estimate excludes the proceeds, if any, from the exercise of Unregistered Warrants being issued in the Warrant Private Placement.

We intend to use the net proceeds from this offering, together with our existing cash and cash equivalents on research, development, working capital and other general corporate purposes.

We may temporarily invest the net proceeds from this offering in investment-grade, interest-bearing securities until they are used for their stated purpose. We have no current commitments or agreements with respect to any material acquisitions and may not make any material acquisitions. We have not determined the amounts we plan to spend on any of the areas listed above or the timing of these expenditures. The occurrence of unforeseen events or changed business conditions, however, could result in the application of the net proceeds from this offering in a manner other than as described in this prospectus supplement. As a result, our management will retain broad discretion over the allocation of the net proceeds from this offering.

Based on our research and development plans and our timing expectations related to the progress of our programs, we expect that the net proceeds from this offering, together with our existing cash and cash equivalents, will enable us to fund our operations into mid-2025. We have based this estimate on assumptions that may prove to be wrong, and it is possible that we will not achieve the progress that we expect with these funds because the actual costs and timing of preclinical and clinical development, regulatory and commercial activities are difficult to predict and are subject to substantial risks and delays, and that we will use our capital resources sooner than we currently expect. This estimate does not reflect any additional expenditures that may result from any further strategic transactions to expand and diversify our product pipeline, including acquisitions of assets, businesses, rights to products, product candidates or technologies or strategic alliances or collaborations that we may pursue.

We will require additional funding to fund the development of emavusertib through regulatory approval and commercialization, and to support our continued operations. We expect to finance our operations through the proceeds of this offering, our sales agreement with Cantor Fitzgerald & Co. and JonesTrading Institutional Services LLC or other potential equity financings, debt financings, strategic transactions or other capital sources. However, we may not be successful in securing additional financing on acceptable terms, or at all. If we are unable to obtain sufficient funding, we will be forced to delay, reduce in scope or eliminate our research and development program for emavusertib, including related clinical trials and operating expenses, potentially delaying the time to market for, or preventing the marketing of, emavusertib, which could adversely affect our business prospects and our ability to continue operations, and would have a negative impact on our financial condition and our ability to pursue our business strategies. See "Risk Factors-We have identified conditions and events that raise substantial doubt about our ability to continue as a going concern" in Part I, Item 1A of our Annual Report on Form 10-K for the fiscal year ended December 31, 2023.
S-11

DILUTION

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

Our net tangible book value on June 30, 2024 was approximately ($9.7 million), or ($1.64) per share. "Net tangible book value" is total assets minus the sum of liabilities and goodwill. "Net tangible book value per share" is net tangible book value divided by the total number of shares outstanding.

After giving effect to the sale of 2,398,414 shares of our common stock in this offering at an offering price of $5.045 per share, and after deducting estimated placement agent fees and estimated offering expenses payable by us, our as adjusted net tangible book value as of June 30, 2024 would have been approximately $1.2 million, or $0.15 per share of common stock. This represents an immediate increase in net tangible book value of $1.78 per share to our existing stockholders and an immediate dilution in net tangible book value of $4.90 per share to investors participating in this offering. The following table illustrates this dilution per share to investors participating in this offering:

Offering price per share

$5.045
Net tangible book value per share as of June 30, 2024
$(1.64)

Increase in net tangible book value per share attributable to investors purchasing
shares of our common stock in this offering
$1.78

As adjusted net tangible book value per share as of June 30, 2024 after giving effect to this offering
$0.15
Dilution per share to investors participating in this offering $4.90
The number of shares of our common stock that will be outstanding immediately after this offering as shown above is based on 5,904,278 shares outstanding as of June 30, 2024 and excludes:
• 1,226,714 shares of our common stock issuable upon the exercise of stock options outstanding as of June 30, 2024, at a weighted average exercise price of $35.23 per share;
• an aggregate of 890,670 shares of common stock reserved for future issuance under our Fifth Amended and Restated 2010 Stock Incentive Plan as of June 30, 2024;
• an aggregate of 415,324 shares of common stock reserved for future issuance under our Amended and Restated 2010 Employee Stock Purchase Plan, as amended, as of June 30, 2024; and
• 168,640 shares of our common stock issued and sold after June 30, 2024 pursuant to our "at-the-market" offering program under our sales agreement with Cantor Fitzgerald & Co. and JonesTrading Institutional Services LLC.

In addition, the discussion and table above do not include (i) the $98.8 million of shares of our common stock that remains available for sale through an "at-the-market equity offering" program under our sales agreement that we entered into with Cantor Fitzgerald & Co. and JonesTrading Institutional Services LLC or (ii) any shares of our common stock issuable upon the exercise of Unregistered Warrants being issued to the investors in the Warrant Private Placement.

To the extent that any options are exercised, new options or other equity awards are issued under our equity incentive plans, or we otherwise issue additional shares of common stock in the future, including pursuant to the sales agreement or stock purchase agreement referenced above, there will be further dilution to new investors.

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DESCRIPTION OF COMMON STOCK

The following description of the material terms of our common stock is intended as a summary only and therefore is not a complete description of our common stock. This description is based upon, and is qualified by reference to, our restated certificate of incorporation, as amended, or our certificate of incorporation, our amended and restated by-laws, as amended, or our by-laws, and applicable provisions of Delaware corporate law. You should read our certificate of incorporation and by-laws, which are filed as exhibits to our Annual Report on Form 10-K for the fiscal year ended December 31, 2023 for the provisions that may be important to you.

Authorized Capital Stock. As of September 30, 2024, our authorized capital stock consists of 34,171,875 shares of common stock and 5,000,000 shares of preferred stock.

Annual Meeting. Annual meetings of our stockholders are held on the date designated in accordance with our by-laws. Written notice must be mailed to each stockholder entitled to vote not less than ten nor more than 60 days before the date of the meeting. The presence in person, by means of remote communication in a manner, if any, authorized by our board of directors in its sole discretion, or by proxy of the holders of record of a majority of our issued and outstanding shares entitled to vote at such meeting constitutes a quorum for the transaction of business at meetings of the stockholders. Special meetings of the stockholders may be called for any purpose or purposes by the chair of the board of directors, chief executive officer (or if there is no chief executive officer, the president) or the board of directors. Except as may be otherwise provided by applicable law, our certificate of incorporation or our by-laws, all elections shall be decided by a plurality, and all other questions shall be decided by a majority, of the votes cast by stockholders entitled to vote thereon at a duly held meeting of stockholders at which a quorum is present.

Voting Rights. For all matters submitted to a vote of stockholders, each holder of common stock is entitled to one vote for each share registered in his or her name on our books. Our common stock does not have cumulative voting rights.

Dividends. If our board of directors declares a dividend, holders of common stock will receive payments from our funds that are legally available to pay dividends. However, this dividend right is subject to any preferential dividend rights we may grant to the holders of preferred stock, if any is outstanding.

Liquidation and Dissolution. If we are liquidated or dissolved, the holders of our common stock will be entitled to share ratably in all the assets that remain after we pay our liabilities and any amounts we may owe to the holders of preferred stock, if any is outstanding.

Other Rights. Holders of the common stock have no right to:
• convert the stock into any other security;
• have the stock redeemed;
• purchase additional stock; or
• maintain their proportionate ownership interest and there are no sinking fund provisions applicable to our common stock.

The rights, preferences and privileges of the holders of common stock are subject to, and may be adversely affected by, the rights of the holders of shares of any series of preferred stock that the Company may designate and issue.

Transfer Agent and Registrar. Computershare Trust Company, N.A. is transfer agent and registrar for the common stock.

Additional information regarding our capital stock, including a description of certain terms of our certificate of incorporation and our by-laws and applicable provisions of Delaware corporate law, is set forth under the caption "Description of Common Stock" beginning on page S-13 of the accompanying prospectus.

Listing on The Nasdaq Capital Market
Our common stock is listed on The Nasdaq Capital Market under the trading symbol "CRIS."


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WARRANT PRIVATE PLACEMENT

In the Warrant Private Placement closing concurrently with the offering, we are selling Unregistered Warrants to purchase up to 2,398,414 shares of our common stock. For each share of our common stock sold in this offering, an accompanying Unregistered Warrant will be issued to the investor thereof. Each Unregistered Warrant will be exercisable for one share of our common stock at an exercise price of $4.92 per share, will be immediately exercisable, and will have a term of exercise equal to five years from the date of issuance.

The Unregistered Warrants and Unregistered Warrant Shares issuable upon the exercise of the Unregistered Warrants are not being registered under the Securities Act, nor are they being offered pursuant to this prospectus supplement and accompanying prospectus. The Unregistered Warrants and Unregistered Warrant Shares are being offered pursuant to the exemption provided in Section 4(a)(2) of the Securities Act and/or Regulation D promulgated thereunder.

Accordingly, the investors in the Warrant Private Placement may exercise the Unregistered Warrants and sell the Unregistered Warrant Shares issuable upon the exercise of such security only 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 or, if and only if there is no effective registration statement registering the resale of the Unregistered Warrant Shares, or no current prospectus available for such shares, the investors may exercise the Unregistered Warrants by means of a "cashless exercise."

If, at the time a holder exercises its Unregistered Warrants, a registration statement registering the Unregistered Warrant Shares under the Securities Act is not then effective or available for the resale of such shares, then 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 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 Unregistered Warrants. No fractional shares will be issued upon the exercise of the Unregistered Warrants. We will, at our election, either pay a cash adjustment in respect of any such final fraction in an amount equal to such fraction multiplied by the exercise price or round up to the next whole share.

We may not effect the exercise of any Unregistered Warrant, and a holder will not have the right to exercise any portion of any Unregistered Warrant if, upon giving effect to such exercise, the aggregate number of shares of our common stock beneficially owned by the holder (together with its affiliates) would exceed 4.99% or 9.99%, as elected by the holder, of the number of shares of our common stock outstanding immediately after giving effect to the exercise, as such percentage ownership is determined in accordance with the terms of such warrant, which percentage may be increased at the holder's election upon 61 days' notice to us subject to the terms of such warrants, provided that such percentage may in no event exceed 9.99% or 19.99%, as elected by the holder.

In certain circumstances, upon a fundamental transaction (as described in the Unregistered Warrants, and generally including any reclassification, reorganization or recapitalization of our common stock; the sale, lease, license, assignment, conveyance, transfer or other disposition of all or substantially all of our assets; our consolidation or merger with or into another person in which we are not the surviving entity, the acquisition of more than 50% of our outstanding common stock; or any person or group becoming the beneficial owner of 50% of the voting power of our outstanding common stock and in connection with such transaction our common stock is converted into or exchanged for other securities, cash or property), the holders of Unregistered Warrants will be entitled to receive upon exercise of the Unregistered Warrants the kind and amount of securities, cash or other property that the holders would have received had they exercised the Unregistered Warrants immediately prior to such fundamental transaction.

Notwithstanding anything to contrary, in certain circumstances, upon certain fundamental transactions, the holders of Unregistered Warrants will have the right to require us or a successor entity to repurchase such warrants at their fair value using a Black Scholes option pricing formula; provided that in the event that (i) the fundamental transaction is not approved by the Board of Directors, and therefore not within our control, and (ii) the alternate consideration payable to holders of common stock in such fundamental transaction consists of equity securities of the successor or acquirer that are quoted or listed on a nationally recognized securities exchange, then the holder of the warrants shall only be entitled to receive the same type or form of consideration (and in the same proportion), determined in accordance with the Black Scholes option pricing formula.

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

The Unregistered Warrants are not and will not be listed for trading on any national securities exchange or any other nationally recognized trading system.
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PLAN OF DISTRIBUTION

We have engaged Truist Securities, Inc. and Laidlaw & Company (UK) Ltd., which we refer to as the placement agents, to act as our placement agents to solicit offers to purchase the securities offered by this prospectus supplement and the accompanying prospectus. Under the terms of an engagement letter between us and each of the placement agents, the placement agents are not purchasing or selling any securities, nor are they required to arrange for the purchase and sale of any specific number or dollar amount of securities, but only to use their best efforts to arrange for the sale of the securities by us. Therefore, we may not sell all of the securities being offered hereby. The terms of this offering were subject to market conditions and negotiations between us and the prospective investors. We have entered into a securities purchase agreement directly with the investors who have agreed to purchase our securities in this offering. We will only sell securities in this offering to such investors.

Delivery of the securities offered hereby is expected to occur on or about October 30, 2024, subject to the satisfaction of customary closing conditions.

Fees and Expenses
We have agreed to pay the placement agents a cash fee equal to 7.719% of the aggregate gross proceeds from the offering. The following table shows the per share and total cash fee we will pay to the placement agents in connection with the sale of our securities offered pursuant to this prospectus supplement and the accompanying prospectus, assuming the purchase of all of the securities offered hereby.


Per Share
Total
Offering price
$5.045
$12,099,999
Placement agent fees(1)
$0.389
$934,000
Proceeds to us, before expenses(2)
$4.656
$11,165,999
(1) We have also agreed to reimburse the placement agents for certain expenses. See below.
(2) The amount of the offering proceeds to us presented in this table does not take into account any proceeds from the exercise of any of the Unregistered Warrants being issued in the Warrant Private Placement.

We estimate expenses payable by us in connection with this offering, other than the placement agent fees referred to above, will be approximately
$200,000. We have also agreed to reimburse the placement agents for up to $80,000 (which may be increased with our written consent) for certain reasonable and documented fees and expenses incurred in connection with this offering, including their counsel fees.

Tail Fee
We have also agreed to pay the placements agents, subject to certain exceptions, a tail fee equal to the compensation due to them in this offering, if we execute an agreement with any investor with whom the placement agents conducted substantive discussions regarding this offering, pursuant to which such investor will participate in any financing, during the three-month period following the closing of this offering.

Indemnification
We have agreed to indemnify the placement agents against certain liabilities, including liabilities under the Securities Act, or to contribute to payments the placement agents may be required to make with respect to any of these liabilities.

Listing
Our common stock is listed on The Nasdaq Capital Market under the trading symbol "CRIS."

No Sales of Similar Securities
We and our executive officers and directors have agreed, subject to specified exceptions, not to directly or indirectly:
• offer, sell, assign, transfer, pledge, contract to sell, or otherwise dispose of (or announce the intention to otherwise dispose of) any shares of common stock, options or warrants to acquire shares of common stock, or securities exchangeable for or exercisable for or convertible into shares of common stock, which we refer to as common stock securities;

• enter into any swap, hedge or similar agreement or arrangement that transfers to another, in whole or in part, the economic consequences of ownership of common stock securities currently or hereafter owned either of record or beneficially; or
• engage in any short selling of common stock securities.

The restriction terminates, with respect to us and our executive officers and directors, after the close of trading of the common stock on and including the 60th and 30th day, respectively, after the date of this prospectus supplement.

Other Activities and Relationships
The placement agents and certain of their affiliates are full service financial institutions engaged in various activities, which may include securities trading, commercial and investment banking, financial advisory, investment management, investment research, principal investment, hedging, financing and brokerage activities. The placement agents and certain of their affiliates have, from time to time, performed, and may in the future perform, various commercial and investment banking and financial advisory services for us and our affiliates, for which they received or will receive customary fees and
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expenses. The placement agents are also acting as the placement agents in the Warrant Private Placement. However, except as disclosed in this prospectus supplement, we have no present arrangements with the placement agents for any further services.

In the ordinary course of their various business activities, the placement agents and certain of their affiliates may make or hold a broad array of investments and actively trade debt and equity securities (or related derivative securities) and financial instruments (including bank loans) for their own account and for the accounts of their customers, and such investment and securities activities may involve securities and/or instruments issued by us and our affiliates. If the placement agents or their affiliates have a lending relationship with us, they routinely hedge their credit exposure to us consistent with their customary risk management policies. The placement agents and their affiliates may hedge such exposure by entering into transactions that consist of either the purchase of credit default swaps or the creation of short positions in our securities or the securities of our affiliates, including potentially the common stock offered hereby. Any such short positions could adversely affect future trading prices of the common stock offered hereby. The placement agents and certain of their affiliates may also communicate independent investment recommendations, market color or trading ideas and/or publish or express independent research views in respect of such securities or instruments and may at any time hold, or recommend to clients that they acquire, long and/or short positions in such securities and instruments.
S-16

MATERIAL U.S. FEDERAL TAX CONSIDERATIONS FOR NON-U.S. HOLDERS OF OUR COMMON STOCK

The following is a discussion of material U.S. federal income and estate tax considerations relating to the ownership and disposition of our common stock by a non-U.S. holder. For purposes of this discussion, the term "non-U.S. holder" means a beneficial owner (other than a partnership or other pass- through entity) of our common stock that is not, for U.S. federal income tax purposes:
• an individual who is a citizen or resident of the United States;
• a corporation, or other entity treated as a corporation for U.S. federal income tax purposes, created or organized in or under the laws of the United States, any state thereof or the District of Columbia;
• an estate the income of which is subject to U.S. federal income taxation regardless of its source; or
• a trust, if a U.S. court is able to exercise primary supervision over the administration of the trust and one or more U.S. persons has authority to control all substantial decisions of the trust or if the trust has a valid election in effect to be treated as a U.S. person under applicable U.S. Treasury Regulations.

This discussion is based on current provisions of the U.S. Internal Revenue Code of 1986, as amended, which we refer to as the Code, existing and proposed U.S. Treasury Regulations promulgated thereunder, current administrative rulings and judicial decisions, as in effect as of the date of this prospectus supplement and all of which are subject to change or to differing interpretation, possibly with retroactive effect. Any change or differing interpretation could alter the tax consequences to non-U.S. holders described in this prospectus supplement. In addition, there can be no assurances that the Internal Revenue Service (IRS) will not challenge one or more of the tax consequences described in this prospectus supplement.

This discussion addresses only non-U.S. holders that hold shares of our common stock as a capital asset (generally, property held for investment). This discussion does not address all aspects of U.S. federal income and estate taxation that may be relevant to a particular non-U.S. holder in light of that non-
U.S. holder's individual circumstances nor does it address the alternative minimum tax, the Medicare tax on net investment income, or any aspects of U.S. state, local or non-U.S. taxes. This discussion also does not consider any specific facts or circumstances that may apply to a non-U.S. holder and does not address the special tax rules applicable to particular non-U.S. holders, such as:
• insurance companies;
• tax-exempt organizations and governmental organizations;
• financial institutions;
• brokers or dealers in securities;
• pension plans;
• controlled foreign corporations;
• passive foreign investment companies;
• owners that hold our common stock as part of a straddle, hedge, conversion transaction, synthetic security or other integrated investment; and
• certain U.S. expatriates.

In addition, this discussion does not address the tax treatment of partnerships or persons who hold their common stock through partnerships or other entities or arrangements that are pass-through entities for U.S. federal income tax purposes. A partner in a partnership or other pass-through entity that will hold our common stock should consult his, her or its own tax advisor regarding the tax consequences of the purchase, ownership and disposition of our common stock through a partnership or other pass-through entity, as applicable.

Prospective investors should consult their own tax advisors regarding the U.S. federal, state, local and non-U.S. income and other tax considerations of acquiring, holding and disposing of our common stock.

Dividends
We do not expect to make cash dividends to holders of common stock in the foreseeable future. If we pay distributions on our common stock, those distributions generally will constitute dividends for U.S. federal income tax purposes to the extent paid from our current or accumulated earnings and profits, as determined under U.S. federal income tax principles. If a distribution exceeds our current and accumulated earnings and profits, the excess will be treated as a tax-free return of the non-U.S. holder's investment, up to such holder's tax basis in the common stock. Any remaining excess will be treated as capital gain, subject to the tax treatment described below under the heading "Gain on Disposition of Common Stock."

Dividends paid to a non-U.S. holder generally will be subject to withholding of U.S. federal income tax at a 30% rate or such lower rate as may be specified by an applicable income tax treaty between the United States and such holder's country of residence. A non-U.S. holder of our common stock who claims the benefit of an applicable income tax treaty between the United States and such holder's country of residence generally will be required to provide a properly executed IRS Form W-8BEN or W-8BEN-E (or successor form) and satisfy applicable certification and other requirements. A non-U.S. holder that is eligible for a reduced rate of U.S. withholding tax under an income tax treaty may obtain a refund or credit of any excess amounts withheld by timely filing an appropriate claim with the IRS. Non-U.S. holders are urged to consult their own tax advisors regarding their entitlement to benefits under an applicable income tax treaty.

Dividends that are treated as effectively connected with a trade or business conducted by a non-U.S. holder within the United States, and, if an applicable income tax treaty so provides, that are attributable to a permanent establishment or a fixed base maintained by the non-U.S. holder within the United States, are generally exempt from the 30% withholding tax if the non-U.S. holder satisfies applicable certification and disclosure requirements. However, such U.S. effectively connected income is taxed on a net income basis at the same U.S. federal income tax rates applicable to United States persons (as
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defined in the Code). Any U.S. effectively connected income received by a non-U.S. holder that is a corporation may also, under certain circumstances, be subject to an additional "branch profits tax" at a 30% rate or such lower rate as may be specified by an applicable income tax treaty between the United States and such holder's country of residence.

Gain on Disposition of Common Stock
A non-U.S. holder generally will not be subject to U.S. federal income tax on gain recognized on a disposition of our common stock unless:
• the gain is effectively connected with the non-U.S. holder's conduct of a trade or business in the United States, and if an applicable income tax treaty so provides, the gain is attributable to a permanent establishment or fixed base maintained by the non-U.S. holder in the United States; in these cases, the non-U.S. holder will be taxed on a net income basis at the same U.S. federal income tax rates applicable to United States persons (as defined in the Code), and if the non-U.S. holder is a foreign corporation, an additional branch profits tax at a 30% rate, or such lower rates as may be specified by an applicable income tax treaty, may also apply;
• the non-U.S. holder is a nonresident alien present in the United States for 183 days or more in the taxable year of the disposition and certain other requirements are met, in which case the non-U.S. holder will be subject to a 30% tax (or such lower rate as may be specified by an applicable income tax treaty) on the net gain derived from the disposition, which may be offset by U.S. source capital losses of the non-U.S. holder, if any; or
• we are or have been, at any time during the five-year period preceding such disposition (or the non-U.S. holder's holding period, if shorter) a "U.S. real property holding corporation" unless our common stock is regularly traded on an established securities market and the non-U.S. holder held no more than 5% of our outstanding common stock, directly or indirectly, during the shorter of the five year period ending on the date of the disposition or the period that the non-U.S. holder held our common stock. If we are determined to be a U.S. real property holding corporation and the non-U.S. holder held more than 5% of our outstanding common stock during the relevant period, then the non-
U.S. holder generally will be taxed on its net gain derived from the disposition at the U.S. federal income tax rates applicable to United States persons (as defined in the Code). Generally, a corporation is a "U.S. real property holding corporation" if the fair market value of its "U.S. real property interests" equals or exceeds 50% of the sum of the fair market value of its worldwide real property interests plus its other assets used or held for use in a trade or business. Although there can be no assurance, we believe that we are not currently, and we do not anticipate becoming, a "U.S. real property holding corporation" for U.S. federal income tax purposes. No assurance can be provided that our common stock will be regularly traded on an established securities market for purposes of the rule described above.

Information Reporting and Backup Withholding
We must report annually to the IRS and to each non-U.S. holder the gross amount of the distributions on our common stock paid to such holder and the tax withheld, if any, with respect to such distributions. Non-U.S. holders may have to comply with specific certification procedures to establish that the holder is not a United States person (as defined in the Code) in order to avoid backup withholding at the applicable rate with respect to dividends on our common stock. Generally, a non-U.S. holder will comply with such procedures if it provides a properly executed IRS Form W-8BEN or W-8BEN-E (or other applicable Form W-8) or otherwise meets documentary evidence requirements for establishing that it is a non-U.S. holder, or otherwise establishes an exemption. Dividends paid to non-U.S. holders subject to withholding of U.S. federal income tax, as described above under the heading "Dividends," will generally be exempt from U.S. backup withholding.

Information reporting and backup withholding generally will apply to the proceeds of a disposition of our common stock by a non-U.S. holder effected by or through the U.S. office of any broker, U.S. or foreign, unless the holder certifies its status as a non-U.S. holder and satisfies certain other requirements, or otherwise establishes an exemption. Generally, information reporting and backup withholding will not apply to a payment of disposition proceeds to a non-U.S. holder where the transaction is effected outside the United States through a non-U.S. office of a broker. However, for information reporting purposes, dispositions effected through a non-U.S. office of a broker with substantial U.S. ownership or operations generally will be treated in a manner similar to dispositions effected through a U.S. office of a broker. Non-U.S. holders should consult their own tax advisors regarding the application of the information reporting and backup withholding rules to them.

Copies of information returns may be made available to the tax authorities of the country in which the non-U.S. holder resides or is incorporated under the provisions of a specific treaty or agreement.

Backup withholding is not an additional tax. Rather, any amounts withheld under the backup withholding rules from a payment to a non-U.S. holder can be refunded or credited against the non-U.S. holder's U.S. federal income tax liability, if any, provided that an appropriate claim is timely filed with the IRS.

FATCA
Provisions of the Code commonly referred to as the Foreign Account Tax Compliance Act, or FATCA, generally impose a 30% withholding tax on dividends on, and gross proceeds from the sale or other disposition of, our common stock if paid to a foreign entity unless (i) if the foreign entity is a "foreign financial institution," the foreign entity undertakes certain due diligence, reporting, withholding, and certification obligations, (ii) if the foreign entity is not a "foreign financial institution," the foreign entity identifies certain of its U.S. investors, or (iii) the foreign entity is otherwise excepted under FATCA.

Withholding under FATCA generally applies to payments of dividends on our common stock. While withholding under FATCA may apply to payments of gross proceeds from a sale or other disposition of our common stock, under proposed U.S. Treasury Regulations, withholding on payments of gross proceeds is not required. Although such regulations are not final, applicable withholding agents may rely on the proposed regulations until final regulations are issued.

If withholding under FATCA is required on any payment related to our common stock, investors not otherwise subject to withholding (or that otherwise would be entitled to a reduced rate of withholding) on such payment may be required to seek a refund or credit from the IRS. An intergovernmental agreement between the United States and an applicable foreign country may modify the requirements described in this section. Non-U.S. holders should
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consult their own tax advisors regarding the possible implications of FATCA on their investment in our common stock and the entities through which they hold our common stock.

U.S. Federal Estate Tax
Common stock owned or treated as owned by an individual who is a non-U.S. holder (as specially defined for U.S. federal estate tax purposes) at the time of death will be included in the individual's gross estate for U.S. federal estate tax purposes and, therefore, may be subject to U.S. federal estate tax, unless an applicable estate tax or other treaty provides otherwise.

The preceding discussion of material U.S. federal tax considerations is for prospective investors' information only. It is not tax advice. Prospective investors should consult their own tax advisors regarding the particular U.S. federal, state, local and non-U.S. tax consequences of purchasing, holding and disposing of our common stock, including the consequences of any proposed changes in applicable laws.
S-19

LEGAL MATTERS

The validity of the issuance of the common stock offered hereby will be passed upon for us by Wilmer Cutler Pickering Hale and Dorr LLP, Boston, Massachusetts. The placement agents are being represented in connection with this offering by Mintz, Levin, Cohn, Ferris, Glovsky and Popeo, P.C., Boston, Massachusetts.


EXPERTS

The financial statements incorporated in this prospectus supplement by reference to the Annual Report on Form 10-K for the year ended December 31, 2023 have been so incorporated in reliance on the report (which contains an explanatory paragraph relating to the Company's ability to continue as a going concern as described in Note 1 to the financial statements) of PricewaterhouseCoopers LLP, an independent registered public accounting firm, given on the authority of said firm as experts in auditing and accounting.

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PROSPECTUS

$300,000,000

Common Stock

We may offer and sell shares of our common stock from time to time in one or more offerings of up to $300,000,000 in aggregate offering price. This prospectus describes the terms of our common stock and the general manner in which our common stock will be offered. We will provide in supplements to this prospectus the specific manner in which our common stock will be offered and may also supplement, update or amend information contained in this document. You should read this prospectus and any applicable prospectus supplement before you invest.
We may offer our common stock in amounts, at prices and on terms determined at the time of offering. Our common stock may be sold directly to you, through agents, or through underwriters and dealers. If agents, underwriters or dealers are used to sell our common stock, we will name them and describe their compensation in a prospectus supplement.
Our common stock is listed on The Nasdaq Capital Market under the symbol "CRIS."
_________________________________________________
Investing in our common stock involves significant risks. See the information included under "Risk Factors" on page 7 of this prospectus and in any accompanying prospectus supplement, and under similar headings in the documents incorporated by reference in this prospectus or any prospectus supplement, for a discussion of the factors you should carefully consider before deciding to purchase our common stock.
_________________________________________________
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 April 12, 2024

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TABLE OF CONTENTS

ABOUT THIS PROSPECTUS SUPPLEMENT
2
WHERE YOU CAN FIND MORE INFORMATION
3
INCORPORATION BY REFERENCE
3
CAUTIONARY NOTE REGARDING FORWARD-LOOKING STATEMENTS AND INDUSTRY DATA
4
CURIS, INC.
6
RISK FACTORS
7
USE OF PROCEEDS
8
DESCRIPTION OF COMMON STOCK
9
PLAN OF DISTRIBUTION
12
LEGAL MATTERS
14
EXPERTS
14

1

ABOUT THIS PROSPECTUS

This prospectus is part of a registration statement that we filed with the Securities and Exchange Commission, which we refer to as the "SEC," utilizing a "shelf" registration process. Under this shelf registration process, we may from time to time sell our common stock described in this prospectus in one or more offerings for an aggregate initial offering price of up to $300,000,000.
This prospectus provides you with a general description of our common stock. Each time we sell our common stock, we will provide one or more prospectus supplements that will contain specific information about the terms of the offering. The prospectus supplement may also add, update or change information contained in this prospectus. You should read both this prospectus and the accompanying prospectus supplement together with the additional information described under the heading "Where You Can Find More Information."
You should rely only on the information contained in or incorporated by reference in this prospectus, any accompanying prospectus supplement or in any related free writing prospectus filed by us with the SEC. We have not authorized anyone to provide you with different information. This prospectus and any accompanying prospectus supplement do not constitute an offer to sell or the solicitation of an offer to buy any securities other than the common stock described in this prospectus or such accompanying prospectus supplement or an offer to sell or the solicitation of an offer to buy such securities in any circumstances in which such offer or solicitation is unlawful. You should assume that the information appearing in this prospectus, any prospectus supplement, the documents incorporated by reference and any related free writing prospectus is accurate only as of their respective dates. Our business, financial condition, results of operations and prospects may have changed materially since those dates.
Unless the context otherwise indicates, references in this prospectus to the "Company," "we," "our" and "us" refer, collectively, to Curis, Inc., a Delaware corporation, and its consolidated subsidiaries.

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WHERE YOU CAN FIND MORE INFORMATION
We file annual, quarterly and current reports, proxy statements and other information with the SEC. Our SEC filings are available to the public over the Internet at the SEC's website at http://www.sec.gov. Copies of certain information filed by us with the SEC are also available on our website at http://www.curis.com. Our website is not a part of this prospectus and is not incorporated by reference in this prospectus.
This prospectus is part of a registration statement we filed with the SEC. This prospectus omits some information contained in the registration statement in accordance with SEC rules and regulations. You should review the information and exhibits in the registration statement for further information about us and our consolidated subsidiaries and the common stock we are offering. Statements in this prospectus concerning any document we filed as an exhibit to the registration statement or that we otherwise filed with the SEC are not intended to be comprehensive and are qualified by reference to these filings and the exhibits attached thereto. You should review the complete document to evaluate these statements.

INCORPORATION BY REFERENCE
The SEC allows us to incorporate by reference much of the information we file with the SEC, which means that we can disclose important information to you by referring you to those publicly available documents. The information that we incorporate by reference in this prospectus is considered to be part of this prospectus. Because we are incorporating by reference future filings with the SEC, this prospectus is continually updated and those future filings may modify or supersede some of the information included or incorporated in this prospectus. This means that you must look at all of the SEC filings that we incorporate by reference to determine if any of the statements in this prospectus or in any document previously incorporated by reference have been modified or superseded. This prospectus incorporates by reference the documents listed below (File No. 000-30347) and any future filings we make with the SEC under Sections 13(a), 13(c), 14 or 15(d) of the Securities Exchange Act of 1934, as amended, or the Exchange Act (in each case, other than those documents or the portions of those documents not deemed to be filed) between the date of the initial registration statement and the effectiveness of the registration statement and following the effectiveness of the registration statement until the offering of common stock under the registration statement is terminated or completed:
•Annual Report on Form 10-Kfor the fiscal year ended December 31, 2023, as filed with the SEC on February 8, 2024; and
•The description of our common stock contained in our Registration Statement on Form 8-Aas filed with the SEC on April 13, 2000, as the description therein has been updated and superseded by the description of our capital stock contained in Exhibit 4.2 to our Annual Report on Form 10-K for the fiscal year ended December 31, 2023, as filed with the SEC on February 8, 2024, and including any amendments and reports filed for the purpose of updating such description.

You may request a copy of these filings, at no cost, by writing or telephoning us at the following address or telephone number:
Curis, Inc.
128 Spring Street
Building C - Suite 500
Lexington, MA 02421
Attn: Corporate Controller
(617) 503-6500
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CAUTIONARY NOTE REGARDING FORWARD-LOOKING STATEMENTS AND INDUSTRY DATA
This prospectus, any accompanying prospectus supplement and the information incorporated by reference in this prospectus and any accompanying prospectus supplement contain certain forward-looking statements within the meaning of Section 27A of the Securities Act of 1933, as amended, or the Securities Act, and Section 21E of the Exchange Act. All statements other than statements of historical fact contained in this prospectus and any accompanying prospectus supplement are statements that could be deemed forward-looking statements, including without limitation any statements with respect to the plans, strategies and objectives of management for future operations; statements concerning product research, development and commercialization plans, timelines and anticipated results; statements of expectation or belief; statements with respect to clinical trials and studies; statements with respect to royalties and milestones; statements with respect to the therapeutic potential of drug candidates; expectations of revenue, expenses, earnings or losses from operations, or other financial results; and statements of assumptions underlying any of the foregoing. Without limiting the foregoing, the words "anticipate(s)", "believe(s)", "focus(es)", "could", "estimate(s)", "expect(s)", "intend(s)", "may", "plan(s)", "seek(s)", "will", "strategy", "mission", "potential", "should","would" and other similar language, whether in the negative or affirmative, are intended to identify forward-looking statements, although not all forward-looking statements contain these identifying words. Forward-looking statements may include, but are not limited to, statements about:
•the initiation, timing, progress and results of future preclinical studies and clinical trials, and our research and development program for emavusertib;
•our estimates of the period in which we anticipate that existing cash, cash equivalents, and investments will enable us to fund our current and planned operations;
•our ability to continue as a going concern;
•our ability to obtain additional financing;
•our ability to establish and maintain collaborations;
•our plans to develop and commercialize emavusertib;
•the timing or likelihood of regulatory filings and approvals;
•the implementation of our business model and strategic plans for our business, emavusertib and technology;
•our estimates regarding expenses, future revenue and capital requirements;
•developments and projections relating to our competitors and our industry;
•our commercialization, marketing and manufacturing capabilities and strategy;
•the rate and degree of market acceptance and clinical utility of our products;
•our competitive position; and
•our intellectual property position.

Because forward-looking statements relate to the future, they are subject to inherent uncertainties, risks and changes in circumstances that are difficult to predict. Our actual results could differ materially from those anticipated in these forward-looking statements as a result of various factors. We therefore caution you against relying on any of these forward-looking statements. These forward-looking statements are only predictions and are subject to risks, uncertainties and assumptions that are referenced in the section of any accompanying prospectus supplement entitled "Risk Factors." You should also carefully review the risk factors, risk factor summary and cautionary statements described in the other documents we file from time to time with the SEC, specifically our most recent Annual Report on Form 10-K, our Quarterly Reports on Form 10-Q and our Current Reports on Form 8-K. If one or more of these factors materialize, or if any underlying assumptions prove incorrect, our actual results, performance or achievements may vary materially from any future results, performance or achievements expressed or implied by these forward-looking statements.
You should consider these factors and the other cautionary statements made in this prospectus, any prospectus supplement and the documents we incorporate by reference herein and therein as being applicable to all related forward-looking statements wherever they appear in this prospectus, any prospectus supplement or the documents incorporated by reference. While we may elect to update forward-looking statements wherever they
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appear in this prospectus, any prospectus supplement or the documents incorporated by reference herein and therein, we do not assume, and specifically disclaim, any obligation to do so, whether as a result of new information, future events or otherwise, except as required by law.
This prospectus, any prospectus supplement and the documents incorporated by reference herein and therein include statistical and other industry and market data that we obtained from industry publications and research, surveys, and studies conducted by third parties as well as our own estimates. All of the market data used in this prospectus, any prospectus supplement and the documents incorporated by reference herein and therein involve a number of assumptions and limitations, and you are cautioned not to give undue weight to such data. Industry publications and third-party research, surveys, and studies generally indicate that their information has been obtained from sources believed to be reliable, although they do not guarantee the accuracy or completeness of such information. Our estimates of the potential market opportunities for our drug candidates include several key assumptions based on our industry knowledge, industry publications, third-party research, and other surveys, which may be based on a small sample size and may fail to accurately reflect market opportunities. While we believe that our internal assumptions are reasonable, no independent source has verified such assumptions.
5

CURIS, INC.
We are a biotechnology company focused on the clinical development of emavusertib, an orally available, small molecule IRAK4 inhibitor. Through our 2015 collaboration with Aurigene, we have the exclusive license to emavusertib (CA-4948). We licensed our rights to Erivedge® to Genentech, a member of the Roche Group, under which they are commercializing Erivedge® for the treatment of advanced basal cell carcinoma.
Our principal executive offices are located at 128 Spring Street, Building C-Suite 500, Lexington, Massachusetts 02421, and our telephone number is (617) 503-6500.
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RISK FACTORS
Investing in our common stock involves a high degree of risk. You should carefully review the risks and uncertainties described under the heading "Risk Factors" contained in the applicable prospectus supplement and any related free writing prospectus, and under similar headings in our Annual Report on Form 10-K for the year ended December 31, 2023, as updated by our subsequent filings, which are incorporated by reference into this prospectus, before deciding whether to purchase any of the common stock being registered pursuant to the registration statement of which this prospectus is a part. Each of the risk factors could adversely affect our business, results of operations, financial condition and cash flows, as well as adversely affect the value of an investment in our common stock, and the occurrence of any of these risks might cause you to lose all or part of your investment. Additional risks not presently known to us or that we currently believe are immaterial may also significantly impair our business operations.
7

USE OF PROCEEDS
We intend to use the net proceeds from the sale of any common stock offered under this prospectus for general corporate purposes unless otherwise indicated in the applicable prospectus supplement. General corporate purposes may include the conducting of further clinical studies and preclinical testing of our product candidates, the funding of other research and development expenses, the in-licensing of individual drug candidates or drug programs, the acquisition of companies or businesses that complement our business, the repayment and refinancing of debt, working capital and capital expenditures. We have not determined the amount of net proceeds to be used specifically for such purposes. As a result, management will retain broad discretion over the allocation of the net proceeds of any offering.
8

DESCRIPTION OF COMMON STOCK
The following description of our common stock is intended as a summary only and therefore is not a complete description of our common stock. This description is based upon, and is qualified by reference to, our certificate of incorporation, our by-laws and applicable provisions of Delaware corporate law. You should read our certificate of incorporation and by-laws, which are filed as exhibits to the registration statement of which this prospectus forms a part, for the provisions that are important to you.
Pursuant to our certificate of incorporation, as amended, and as of the date of effectiveness of the registration statement of which this prospectus forms a part, our authorized capital stock consists of 22,781,250 shares of common stock, par value $0.01 per share, and 5,000,000 shares of preferred stock, par value $0.01 per share.
Common Stock
Annual Meeting. Annual meetings of our stockholders are held on the date designated in accordance with our by-laws. Written notice must be mailed to each stockholder entitled to vote not less than ten nor more than 60 days before the date of the meeting. The presence in person, by means of remote communication in a manner, if any, authorized by our board of directors in its sole discretion, or by proxy of the holders of record of a majority of our issued and outstanding shares entitled to vote at such meeting constitutes a quorum for the transaction of business at meetings of the stockholders. Special meetings of the stockholders may be called for any purpose or purposes by the chair of the board of directors, chief executive officer (or if there is no chief executive officer, the president) or the board of directors. Except as may be otherwise provided by applicable law, our certificate of incorporation or our by-laws, all elections shall be decided by a plurality, and all other questions shall be decided by a majority, of the votes cast by stockholders entitled to vote thereon at a duly held meeting of stockholders at which a quorum is present.
Voting Rights. For all matters submitted to a vote of stockholders, each holder of common stock is entitled to one vote for each share registered in his or her name on our books. Our common stock does not have cumulative voting rights.
Dividends. If our board of directors declares a dividend, holders of common stock will receive payments from our funds that are legally available to pay dividends. However, this dividend right is subject to any preferential dividend rights we may grant to the holders of preferred stock, if any is outstanding.
Liquidation and Dissolution. If we are liquidated or dissolved, the holders of our common stock will be entitled to share ratably in all the assets that remain after we pay our liabilities and any amounts we may owe to the holders of preferred stock, if any is outstanding.
Other Rights. Holders of the common stock have no right to:
•convert the stock into any other security;
•have the stock redeemed;
•purchase additional stock; or
•maintain their proportionate ownership interest and there are no sinking fund provisions applicable to our common stock.
The rights, preferences and privileges of the holders of common stock are subject to, and may be adversely affected by, the rights of the holders of shares of any series of preferred stock that the Company may designate and issue.
Transfer Agent and Registrar. Computershare Trust Company, N.A. is transfer agent and registrar for the common stock.
Listing on the Nasdaq Capital Market. Our common stock is listed on the Nasdaq Capital Market under the trading symbol "CRIS."

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Provisions of Our Certificate of Incorporation and By-laws and Delaware Law That May Have Anti-Takeover Effects
Certain provisions of our certificate of incorporation and by-laws may have the effect of making it more difficult for a third party to acquire, or of discouraging a third party from attempting to acquire, control of us.Such provisions could limit the price that certain investors might be willing to pay in the future for shares of our common stock and may limit the ability of stockholders to remove current management or directors or approve transactions that stockholders may deem to be in their best interest and, therefore, could adversely affect the price of our common stock.
No Cumulative Voting.The Delaware General Corporation Law, or the DGCL, provides that stockholders are not entitled to the right to accumulate votes in the election of directors unless our certificate of incorporation provides otherwise.Our certificate of incorporation does not provide for cumulative voting.
Board of Directors. Our by-laws provide for a board of directors divided as nearly equally as possible into three classes. Each class is elected to a term expiring at the annual meeting of stockholders held in the third year following the year of such election. The number of directors comprising our board of directors is fixed from time to time by the board of directors.
Removal of Directors by Stockholders. Our by-laws provide that directors may be removed only for cause by the affirmative vote of the holders of 75% of the shares of our capital stock issued, outstanding and entitled to vote.
Advance Notice Provisions. Our by-laws provide that a stockholder must notify us in writing, within timeframes specified in the by-laws, of any stockholder nomination of a director and of any other business that the stockholder intends to bring at a meeting of stockholders.
No Action by Written Consent. Our certificate of incorporation provides that our stockholders may not act by written consent and may only act at duly called meetings of stockholders; and that the affirmative vote of the holders of at least 75% of the shares of capital stock issued and outstanding and entitled to vote shall be required to amend or repeal, or to adopt any provision inconsistent with, the provision of our certificate of incorporation prohibiting stockholders from acting by written consent.
Amendment to By-laws. Our by-laws may be altered, amended or repealed, or new by-laws may be adopted, by a majority vote of our board of directors or by the affirmative vote of the holders of a majority of our capital stock issued and outstanding and entitled to vote. In addition, the affirmative vote of the holders of at least 75% of the shares of our capital stock issued and outstanding and entitled to vote shall be required to amend or repeal, or to adopt any provision inconsistent with the provisions of our by-laws related to the powers, number, term, classification, committees, the conduct of business at meetings, action by written consent, removal and filling of vacancies with respect to our board of directors; the calling of special meetings of stockholders; the nomination of directors; notice of business at an annual meeting and any provision relating to the amendment of the by-laws.
Undesignated Preferred Stock.Our board of directors has the ability to issue preferred stock with voting or other rights or preferences that could impede the success of any attempt to change control of our company.These and other provisions may have the effect of deferring hostile takeovers or delaying changes in control or management of us.
These provisions of Delaware law, our certificate of incorporation and our by-laws may have the effect of deterring hostile takeovers or delaying changes in our control or in our management.These provisions are intended to enhance the likelihood of continued stability in the composition of our board of directors and in the policies they implement, and to discourage certain types of transactions that may involve an actual or threatened change of our control.These provisions are designed to reduce our vulnerability to an unsolicited acquisition proposal.The provisions also are intended to discourage certain tactics that may be used in proxy fights.However, such provisions could have the effect of discouraging others from making tender offers for our shares and, as a consequence, they also may inhibit fluctuations in the market price of our shares that could result from actual or rumored takeover attempts.
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Exclusive Forum Selection. Our certificate of incorporation provides that, unless we consent in writing to the selection of an alternative forum, the Court of Chancery of the State of Delaware (or if the Court of Chancery does not have jurisdiction, the federal district court for the District of Delaware) shall be the sole and exclusive forum for (1) any derivative action or proceeding brought on behalf of our company, (2) any action asserting a claim of breach of a fiduciary duty owed by any of our current or former directors, officers, other employees or stockholders of our company to our company or to our stockholders, (3) any action asserting a claim against our company arising pursuant to any provision of the DGCL or as to which the DGCL confers jurisdiction on the Court of Chancery, or (4) any action asserting a claim against our company pursuant to any provision of our certificate of incorporation or by-laws or 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.
Delaware Business Combination Statute. We are subject to Section 203 of the DGCL, or Section 203, which prohibits a Delaware corporation from engaging in business combinations with an interested stockholder. An interested stockholder is generally defined as an entity or person beneficially owning 15% or more of the outstanding voting stock of the corporation or any entity or person affiliated with or controlling or controlled by such entity or person.Section 203 provides that an interested stockholder may not engage in business combinations with the corporation for a period of three years after the date that such stockholder became an interested stockholder, with the following exceptions:
•before such date, the board of directors of the corporation approved either the business combination or the transaction that resulted in the stockholder becoming an interested stockholder;
•upon completion 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 began, excluding for purposes of determining the voting stock outstanding (but not the outstanding voting stock owned by the interested stockholder) those shares owned (i) by persons who are directors and also officers and (ii) employee stock plans in which employee participants do not have the right to determine confidentially whether shares held subject to the plan will be tendered in a tender or exchange offer; or
•on or after such date, the business combination is approved by the board of directors and authorized at an annual or special meeting of the stockholders, and not by written consent, by the affirmative vote of at least 66 2/3% of the outstanding voting stock that is not owned by the interested stockholder.

In general, Section 203 defines business combinations to include the following:
•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 certain exceptions, any transaction that results in the issuance or transfer by the corporation of any stock of the corporation to the interested stockholder;
•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 by or through the corporation.
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PLAN OF DISTRIBUTION
We may sell our common stock:
•through underwriters;
•through dealers;
•through agents;
•directly to purchasers; or
•through a combination of any of these methods of sale.
In addition, we may issue our common stock as a dividend or distribution to our existing security holders. This prospectus may be used in connection with any offering of our common stock through any of these methods or other methods described in the applicable prospectus supplement.
We may directly solicit offers to purchase our common stock, or agents may be designated to solicit such offers. We will, in the prospectus supplement relating to such offering, name any agent that could be viewed as an underwriter under the Securities Act, and describe any commissions that we must pay. Any such agent will be acting on a best efforts basis for the period of its appointment or, if indicated in the applicable prospectus supplement, on a firm commitment basis.
The distribution of our common stock may be effected from time to time in one or more transactions:
•at a fixed price, or prices, which may be changed from time to time;
•at market prices prevailing at the time of sale;
•at prices related to such prevailing market prices; or
•at negotiated prices.
Each prospectus supplement will describe the method of distribution of our common stock and any applicable restrictions.
The prospectus supplement will describe the terms of the offering of our common stock, including the following:
•the name of the agent or any underwriters;
•the public offering or purchase price and the proceeds we will receive from the sale of the common stock;
•any discounts and commissions to be allowed or re-allowed or paid to the agent or underwriters;
•all other items constituting underwriting compensation;
•any discounts and commissions to be allowed or re-allowed or paid to dealers; and
•the exchange on which the common stock will be listed.
If any underwriters or agents are utilized in the sale of the common stock in respect of which this prospectus is delivered, we will enter into an underwriting agreement or other agreement with them at the time of sale to them, and we will set forth in the prospectus supplement relating to such offering the names of the underwriters or agents and the terms of the related agreement with them.
If a dealer is utilized in the sale of the common stock in respect of which this prospectus is delivered, we will sell such common stock to the dealer, as principal. The dealer may then resell such common stock to the public at varying prices to be determined by such dealer at the time of resale.
Remarketing firms, agents, underwriters, dealers and other persons may be entitled under agreements which they may enter into with us to indemnification by us against certain civil liabilities, including liabilities under the Securities Act, and may be customers of, engage in transactions with or perform services for us in the ordinary course of business.
If we offer common stock in a subscription rights offering to our existing security holders, we may enter into a standby underwriting agreement with dealers, acting as standby underwriters. We may pay the standby underwriters a commitment fee for the common stock they commit to purchase on a standby basis. If we do not enter
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into a standby underwriting arrangement, we may retain a dealer manager to manage a subscription rights offering for us.
If so indicated in the applicable prospectus supplement, we will authorize underwriters or other persons acting as our agents to solicit offers by certain institutions to purchase common stock from us pursuant to delayed delivery contracts providing for payment and delivery on the date stated in the prospectus supplement. Each contract will be for an amount not less than, and the aggregate amount of common stock sold pursuant to such contracts shall not be less nor more than, the respective amounts stated in the prospectus supplement. Institutions with whom the contracts, when authorized, may be made include commercial and savings banks, insurance companies, pension funds, investment companies, educational and charitable institutions and other institutions, but shall in all cases be subject to our approval. Delayed delivery contracts will not be subject to any conditions except that:
•the purchase by an institution of the common stock covered under that contract shall not at the time of delivery be prohibited under the laws of the jurisdiction to which that institution is subject; and
•if the common stock is also being sold to underwriters acting as principals for their own account, the underwriters shall have purchased such common stock not sold for delayed delivery. The underwriters and other persons acting as our agents will not have any responsibility in respect of the validity or performance of delayed delivery contracts.
Certain agents, underwriters and dealers, and their associates and affiliates may be customers of, have borrowing relationships with, engage in other transactions with, and/or perform services, including investment banking services, for us or one or more of our respective affiliates in the ordinary course of business.
In order to facilitate the offering of our common stock, any underwriters may engage in transactions that stabilize, maintain or otherwise affect the price of our common stock. Specifically, any underwriters may overallot in connection with the offering, creating a short position for their own accounts. In addition, to cover overallotments or to stabilize the price of our common stock, the underwriters may bid for, and purchase our common stock in the open market. Finally, in any offering of our common stock through a syndicate of underwriters, the underwriting syndicate may reclaim selling concessions allowed to an underwriter or a dealer for distributing the common stock in the offering if the syndicate repurchases previously distributed common stock in transactions to cover syndicate short positions, in stabilization transactions or otherwise. Any of these activities may stabilize or maintain the market price of the common stock above independent market levels. Any such underwriters are not required to engage in these activities and may end any of these activities at any time.
As of the date of this prospectus, under Rule 15c6-1 of the Exchange Act, trades in the secondary market generally are required to settle in two business days, unless the parties to any such trade expressly agree otherwise or the securities are sold by us to an underwriter in a firm commitment underwritten offering. The applicable prospectus supplement may provide that the original issue date for your common stock may be more than two scheduled business days after the trade date for your common stock. Accordingly, in such a case, if you wish to trade common stock on any date prior to the second business day before the original issue date for your common stock, you will be required, by virtue of the fact that your common stock initially is expected to settle in more than two scheduled business days after the trade date for your common stock, to make alternative settlement arrangements to prevent a failed settlement. In February 2023, Rule 15c6-1 of the Exchange Act was amended to require, effective May 28, 2024, trades in the secondary market to settle in one business day, unless the parties to any such trade expressly agree otherwise or the securities are sold by us to an underwriter in a firm commitment underwritten offering. Therefore, for any securities offered under this prospectus on or after May 28, 2024, the same process described in this paragraph will apply, except that purchasers who wish to trade such securities on any date prior to the first business day before the original issue date will be required, by virtue of the fact that their securities initially are expected to settle in more than one scheduled business day after the trade date for their securities, to make alternative settlement arrangements to prevent a failed settlement as described in this paragraph.
We can make no assurance as to the liquidity of or the existence of trading markets for the common stock.
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LEGAL MATTERS
Unless the applicable prospectus supplement indicates otherwise, the validity of the common stock in respect of which this prospectus is being delivered will be passed upon by Wilmer Cutler Pickering Hale and Dorr LLP.
EXPERTS
The financial statements incorporated in this Prospectus by reference to the Annual Report on Form 10-K for the year ended December 31, 2023 have been so incorporated in reliance on the report (which contains an explanatory paragraph relating to the Company's ability to continue as a going concern as described in Note 1 to the financial statements) of PricewaterhouseCoopers LLP, an independent registered public accounting firm, given on the authority of said firm as experts in auditing and accounting.
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2,398,414 Shares




Common Stock




PROSPECTUS SUPPLEMENT




TRUIST SECURITIES
LAIDLAW & COMPANY (UK) LTD.










Prospectus Supplement dated October 28, 2024