Freeline Announces Executive Leadership Changes

Freeline Therapeutics Holdings plc (Nasdaq: FRLN) (the "Company" or "Freeline"), a clinical-stage biotechnology company developing transformative AAV-mediated gene therapies for patients suffering from inherited systemic debilitating diseases, today announced the expansion of its executive leadership team with the appointment of James "Jay" Bircher as Chief Technical Operations Officer effective July 1, 2021. Mr. Bircher brings nearly three decades of operational excellence in leadership roles across a wide range of pharmaceutical, biotechnology and medical device manufacturing platforms, including AAV gene therapy.

Mr. Bircher will report to Chief Executive Officer Theresa Heggie as part of the executive leadership team. He will bring to Freeline his deep experience leading manufacturing site teams through successful regulatory inspections conducted by the US Food and Drug Administration ("FDA"), including the Center for Biologics Evaluation and Research ("CBER"), the Center for Drug Evaluation and Research ("CDER"), the European Medicines Agency ("EMA") and other regulatory agencies.

"Jay's deep knowledge base across manufacturing platforms, compliance, validation, quality control and regulatory matters adds tremendous value to Freeline," said Theresa Heggie, Chief Executive Officer of Freeline. "We are building a world-class gene therapy company, with a leadership team that has the strength, experience and vision to realize the potential of our leading capsid and platform technology. Jay's expertise in AAV gene therapies and successful manufacturing track record will help enhance the Company's ability to advance our gene therapy candidates from the clinic to commercialization."

Mr. Bircher said, "I am excited to join Freeline now as the Company gains momentum with plans for a third program in the clinic by the end of this year. Freeline has developed industry-leading AAV platform technology and manufacturing capabilities, which together offer the possibility of delivering potentially transformative medicines that could greatly improve patients' lives."

The Company also announced that Chief Scientific Officer ("CSO"), Romuald Corbau, PhD, has decided to leave Freeline to pursue other opportunities. Dr. Corbau will continue in his current role until August 20, 2021, to facilitate the smooth transition of his responsibilities. Freeline has begun an international search for his replacement.

Amit Nathwani, MD, PhD, who previously served as the CSO of Freeline, will assume the CSO role on an interim basis. Professor Nathwani, who is the Company's co-founder, Scientific Advisor and a member of the Board of Directors, has conducted pioneering research on gene therapy in Hemophilia B.

Ms. Heggie added, "I thank Romu for his many contributions to Freeline, including building a stellar team of scientists whose protein engineering and other complementary expertise have been instrumental in the development and maturation of our differentiated platform technology. We are pleased that Amit will be stepping into an interim role as we undertake a comprehensive search for the next CSO."

About James "Jay" Bircher

Mr. Bircher joins Freeline from Abeona Therapeutics, where he held several roles of increasing responsibility, serving most recently as the company's Chief Technology Officer leading Process Development, Assay Development, Quality, Validation, Manufacturing, Facilities, CMC Program Management and Supply Chain. Before Abeona, he was Head of Quality at Becton, Dickinson and Company (BD), where he led the company from the groundbreaking of a 120,000-square-foot sterile manufacturing facility to an FDA pre-approval inspection and the eventual launch of several ready-to-administer, prefilled syringe products. Later in his tenure at BD, Mr. Bircher served as Head of Manufacturing, where he was responsible for all formulation, fill and packaging operations. He also held positions of increasing responsibility related to quality with GlaxoSmithKline, Amgen and Tyco Healthcare. Mr. Bircher has a Bachelor of Science degree from Marshall University and is Six Sigma certified.

About Freeline Therapeutics

Freeline is a clinical-stage biotechnology company developing transformative adeno-associated virus ("AAV") vector-mediated systemic gene therapies. The Company is dedicated to improving patient lives through innovative, one-time treatments that provide functional cures for inherited systemic debilitating diseases. Freeline uses its proprietary, rationally-designed AAV vector, along with novel promoters and transgenes, to deliver a functional copy of a therapeutic gene into human liver cells, thereby expressing a persistent functional level of a missing protein into the patient's bloodstream. The Company's integrated gene therapy platform includes in-house capabilities in research, clinical development, manufacturing and commercialization. The Company has clinical programs in Hemophilia B, Fabry disease and Gaucher disease Type 1, as well as a preclinical program in Hemophilia A. Freeline is headquartered in the UK and has operations in Germany and the US.