FLT201 is the first AAV gene therapy program to enter the clinic for GaucherdiseaseType 1

FLT201 Phase 1/2 trial for Gaucher disease Type 1 on track for patient dosing in the first half of 2022

LONDON, UK I January 06, 2022 I 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 that the U.S. Food and Drug Administration (FDA) has cleared its Investigational New Drug (IND) application for FLT201 as an investigational gene therapy for the treatment of Gaucher disease Type 1.

“The FDA clearance of this IND is an important milestone for FLT201, which is the first AAV-mediated gene therapy for patients with Gaucher disease Type 1 in the clinic,” said Michael Parini, Chief Executive Officer of Freeline. “Our FLT201 program harnesses our unique scientific platform capabilities – our highly potent, proprietary AAVS3 capsid, robust CMC and pre-clinical data across all our programs, and our advanced protein engineering capabilities – to develop a potentially transformative treatment for patients suffering from Gaucher disease. The entry of our third program into the clinic is important validation of the advantage of Freeline’s portfolio approach to development.”

“This IND clearance is an important step toward bringing FLT201 to patients and is made possible by the extended safety database across our proprietary platform,” said Dr. Pamela Foulds, Chief Medical Officer of Freeline. “Our extensive preclinical proof-of-concept studies suggest FLT201 has the potential to reach difficult to treat tissues, such as bone marrow and lung, which are not sufficiently addressed by standard-of-care enzyme replacement therapy. These data, along with the promise of sustained, endogenous production of GCase following a one-time intravenous infusion, suggest that treatment with FLT201 may be a transformative treatment that can significantly reduce or eliminate the need for enzyme or substrate replacement therapy.”

FLT201 consists of a potent, rationally designed AAV capsid (AAVS3) containing an expression cassette that encodes for a novel glucocerebrosidase variant (GCasevar85) under the control of a liver-specific promoter. The GCasevar85 contains two novel amino acid substitutions to the wild-type human GCase, which results in a 20-fold increase in GCase half-life at lysosomal pH conditions, but similar catalytic parameters to those of wild-type GCase and enzyme replacement therapy (ERT).

Freeline initiated the Phase 1/2 dose-finding trial of FLT201 at the end of 2021 in Europe and expects to dose two patients in the first dose cohort in the first half of 2022, with initial safety and biomarker data from the first cohort expected in Q3 2022. The Company expects to report data on all dosed patients, including those dosed in Q3, prior to year-end 2022.

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 the missing or dysfunctional 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. Freeline is headquartered in the UK and has operations in Germany and the US.

About Gaucher Disease

Gaucher disease is a genetic disorder in which a fatty substance called glucosylceramide accumulates in macrophages in certain organs due to the lack of functional glucocerebrosidase (GCase). The disorder is hereditary and presents in various subtypes. Freeline is currently focused on Gaucher disease Type 1, the most common type, which impacts the health of many organs of the body including the spleen, liver, blood system and bones. The current standard of care is intravenous infusion of ERT every two weeks, which is a significant treatment burden on the patient.

SOURCE: Freeline Therapeutics