Freeline Therapeutics Holdings plc announced that new clinical data from its ongoing Phase 1/2 GALILEO-1 trial of FLT201, its adeno-associated virus (AAV) gene therapy candidate for Gaucher disease, show a substantial reduction of glucosylsphingosine (lyso-Gb1) levels in the blood of the first patient treated with FLT201. Lyso-Gb1 is a well-established biomarker of clinical response in Gaucher disease, with reductions in lyso-Gb1 correlating with positive clinical outcomes. These data are being highlighted in an oral presentation at the European Society of Gene & Cell Therapy (ESGCT) 30th Annual Congress held in Brussels, Belgium. The oral presentation at ESGCT builds on recently reported initial clinical data from the first two patients
treated with FLT201, which demonstrated a favorable safety and tolerability profile, robust increases in plasma levels of glucocerebrosidase (GCase), the enzyme that is deficient in people with Gaucher disease, and normalization of cellular GCase activity. The GCase deficiency in Gaucher disease leads to a buildup of harmful substrates glucosylceramide (Gb-1) and lyso-Gb1, causing symptoms including enlarged spleen and liver, low blood counts, bone pain and reduced lung function. FLT201 is a potential first- and best-in-class gene therapy for Gaucher disease, said Pamela Foulds, M.D.,
Freelines Chief Medical Officer. It is designed to deliver a continuous supply of the enzyme missing in people with Gaucher disease and to deliver a longer-acting version of that enzyme, with the aim of getting enzyme into all disease-affected tissues and increasing the amount of time the enzyme is in those tissues to do its job of clearing harmful substrates. The clinical data to date tell us that FLT201 is expressing high levels of GCase
into the plasma, which is then taken up by cells and which now appears.