EXHIBIT 99.1 REGENXBIO Reports First Quarter 2025 Financial Results and Recent Operational Highlights ROCKVILLE, Md., May 12, 2025 (PR Newswire) -- REGENXBIO Inc. (Nasdaq: RGNX) today reported financial results and recent operational highlights for the first quarter ended March 31, 2025. "We have made tremendous progress towards delivering multiple commercial gene therapies, starting this year," said Curran M. Simpson, President and Chief Executive Officer of REGENXBIO. "Each of our late-stage assets is dem ...