For more information, please visit www.generationbio.com. Exhibit 99.1 Generation Bio Announces Third Quarter 2025 Financial Results CAMBRIDGE, MASS., November 5, 2025 -- Generation Bio Co. (Nasdaq: GBIO), a biotechnology company, today reported third quarter financial results. Third Quarter 2025 Financial Results About Generation Bio Generation Bio is a biotechnology company that was historically working to change what's possible for people living with T cell-driven autoimmune diseases. In August 2025, the ...