Freeline Therapeutics Holdings plc is a biotechnology company that creates gene therapies for inherited debilitating diseases, such as hemophilia B, Fabry disease, and type 1 Gaucher disease. Their main product candidate, verbrinacogene setparvovec (FLT180a), is currently being tested in Phase 1/2 clinical trials for adult male patients with hemophilia B. Their research extends to other indications for systemic gene therapy, and the company is based in Stevenage, UK.