Management Change/Compensation Form 8 K

On August 1, 2024, REGENXBIO Inc. (the "Company") made a one-timegrant of restricted stock units ("RSUs") to Stephen Pakola, M.D., the Company's EVP, Chief Medical Officer, and Olivier Danos, Ph.D., the Company's EVP, Chief Scientific Officer, to promote stability in our leadership team during a period of CEO transition. Dr. Pakola received a grant of 58,386 RSUs and Dr. Danos received a grant of 58,867 RSUs. The RSUs will vest over a two-yearperiod, with one-fourthof the RSUs vesting every six months from the grant date, subject to Dr. Pakola's and Dr. Danos' respective continued service to the Company throughout the vesting period.