Company: RGNX
Filing Date: 2025-04-08
Form Type: DEF 14A
Source: 0000950170-25-052069
Chunk: 132

Company: REGENXBIO Inc.
Filing Date: 2025-04-08
Form: DEF 14A
Chunk 132
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(s) appear(sn signing as attorney, executor, administrator, or other fiduciary, please give full title as such. Joint owners should each sign personally. All holders must sign. If a corporation or partnership, please sign in full corporate or partnership name by authorized officer.

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Important Notice Regarding the Availability of Proxy Materials for the Annual Meeting: The Notice and Proxy Statement and Annual Report are available at www.proxyvote.com. V69760-P25237 REGENXBIO INC. Annual Meeting of Stockholders May 30, 2025 This Proxy is Solicited on Behalf of the Board of Directors The stockholder(s) hereby appoint(s) Curran Simpson and Patrick J. Christmas, or either of them, as proxies, each with the power to appoint his substitute, and hereby authorize(s) them to represent and to vote, as designated on the reverse side of this ballot, all of the shares of Common Stock of REGENXBIO Inc. that the stockholder(s) is/are entitled to vote at the Annual Meeting of Stockholders to be held on May 30, 2025 at 9:00 a.m. Eastern Time, at 9804 Medical Center Drive, Rockville, Maryland 20850, and any adjournment or postponement thereof. This proxy, when properly executed, will be voted in the manner directed herein. If no such direction is made, this proxy will be voted in accordance with the Board of Directors' recommendations. The proxies will vote in their discretion upon any and all other matters that may properly come before the meeting and any adjournment or postponement thereof. Please mark, sign, date and return this proxy card promptly using the enclosed reply envelope. CONTINUED AND TO BE SIGNED ON REVERSE SIDE

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