X0306 4 2020-01-02 false 0001590877 REGENXBIO Inc. RGNX 0001701180 Danos Olivier C/O REGENXBIO INC. 9600 BLACKWELL ROAD, SUITE 210 ROCKVILLE MD 20850 false true false false Chief Scientific Officer Stock Option (Right to Buy) 38.99 2020-01-02 4 A false 48000.00 0.00 A 2030-01-02 Common Stock 48000.00 48000.00 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, 2021 while the optionee provides continuous service to the Issuer. /s/ Patrick J. Christmas as attorney-in-fact 2020-01-06