GBIO Generation Bio Company

Generation Bio Co. (Nasdaq: GBIO), an innovative genetic medicines company creating a new class of non-viral gene therapy, today announced three digital presentations at the American Society of Gene & Cell Therapy (ASGCT) 2021 Virtual Annual Meeting taking place May 11-14. The presentations will cover data supporting use of the company’s platform for antibody gene therapy, a summary of previously released preclinical data from the hemophilia A program and insight into ceDNA construct engineering for factor VIII.

“We look forward to sharing preclinical data supporting the broad potential of our platform in antibody gene therapy and to providing an overview of our lead hemophilia A program,” said Matthew Stanton, Ph.D., chief scientific officer of Generation Bio. “The hemophilia A program is on track and we continue to expect additional non-human primate data by mid-year.”

Digital presentations will be available online to registered attendees beginning May 11.

Generation Bio will present:

• Vector Optimization for Non-Viral Antibody Gene Therapy and Expression of Human Monoclonal Antibodies in Mice
• Non-Viral Gene Delivery of Human FVIII to Hemophilia A Mice and Non-Human Primates
• When Size Matters: FVIII Construct Optimization Leveraging ceDNA, a Non-Viral Gene Therapy Platform

About Generation Bio

Generation Bio is an innovative genetic medicines company focused on creating a new class of non-viral gene therapy to provide durable, redosable treatments for people living with rare and prevalent diseases. The company’s non-viral platform incorporates a proprietary, high-capacity DNA construct called closed-ended DNA, or ceDNA; a cell-targeted lipid nanoparticle delivery system, or ctLNP; and an established, scalable capsid-free manufacturing process. The platform is designed to enable multi-year durability from a single dose of ceDNA and to allow titration and redosing if needed. The ctLNP is designed to deliver large genetic payloads, including multiple genes, to specific tissues to address a wide range of indications. The company’s efficient, scalable manufacturing process supports Generation Bio’s mission to extend the reach of gene therapy to more people, living with more diseases, in more places around the world.

For more information, please visit www.generationbio.com.

Forward-Looking Statements

Any statements in this press release about future expectations, plans and prospects for the company, including statements about our strategic plans or objectives, our technology platforms, our research and clinical development plans, and other statements containing the words “believes,” “anticipates,” “plans,” “expects,” and similar expressions, constitute forward-looking statements within the meaning of The Private Securities Litigation Reform Act of 1995. Actual results may differ materially from those indicated by such forward-looking statements as a result of various important factors, including: uncertainties inherent in the identification and development of product candidates, including the conduct of research activities, the initiation and completion of preclinical studies and clinical trials and clinical development of the company’s product candidates; uncertainties as to the availability and timing of results from preclinical studies and clinical trials; whether results from preclinical studies will be predictive of the results of later preclinical studies and clinical trials; expectations for regulatory approvals to conduct trials or to market products; challenges in the manufacture of genetic medicine products; whether the company’s cash resources are sufficient to fund the company’s operating expenses and capital expenditure requirements for the period anticipated; the impact of the COVID-19 pandemic on the company’s business and operations; as well as the other risks and uncertainties set forth in the “Risk Factors” section of our most recent annual report on Form 10-K, which is on file with the Securities and Exchange Commission, and in subsequent filings the company may make with the Securities and Exchange Commission. In addition, the forward-looking statements included in this press release represent the company’s views as of the date hereof. The company anticipates that subsequent events and developments will cause the company’s views to change. However, while the company may elect to update these forward-looking statements at some point in the future, the company specifically disclaims any obligation to do so. These forward-looking statements should not be relied upon as representing the company’s views as of any date subsequent to the date on which they were made.

Contacts:

InvestorsMaren KillackeyGeneration Bio541-646-2420mkillackey@generationbio.com

MediaAlicia WebbGeneration Bio847-254-4275awebb@generationbio.com

Stephanie SimonTen Bridge Communications617-581-9333stephanie@tenbridgecommunications.com