X0508 4/A 2025-01-02 2025-01-06 false 0001590877 REGENXBIO Inc. RGNX 0001346164 Simpson Curran C/O REGENXBIO INC. 9804 MEDICAL CENTER DRIVE ROCKVILLE MD 20850 true true false false Chief Executive Officer false Stock Options (Right to buy) 7.86 2025-01-02 4 A false 478606.00 0.00 A 2035-01-02 Common Stock 478606.00 478606.00 D 25% of the shares subject to this option shall vest after 12 months of continuous service with the Issuer. The balance will vest in equal monthly installments over the 36 months following January 2, 2026 while the optionee provides continuous service to the Issuer. The original Form 4, filed on January 6, 2025, is being amended by this Form 4 amendment solely to correct a share calculation error on the part of the Issuer, which misreported the amount of stock options granted to the reporting person as 476,606. /s/ Patrick J. Christmas as attorney-in-fact 2025-01-14