EXHIBIT 23.1

CONSENT OF INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM

We hereby consent to the incorporation by reference in the Registration Statements on Form S-3 (No. 333-226691) and Form S-8 (No. 333-223466, 333-216508, 333-209899, 333-206984) of REGENXBIO Inc. of our report dated February 27, 2019 relating to the financial statements and the effectiveness of internal control over financial reporting, which appears in this Form 10-K.

/s/ PricewaterhouseCoopers LLPMcLean, VirginiaFebruary 27, 2019