Robert J. Hopkin, MD, on Assessing ST-920 for Fabry Disease

“We have not had a big inflammatory reaction. In fact, no patients have required prolonged hospitalization, intensive monitoring, or medications to suppress inflammation against either the α-galactosidase A protein that's produced or against the vector that's modified from the AAV viruses. That is actually a huge deal because one of the limiting factors on implementation of gene therapy has been the triggering of the immune system and the [adverse] effects related to that.”

Fabry disease is a rare lysosomal storage disease caused by a deficiency of the enzyme α-galactosidase A (a-Gal A). Sangamo Therapeutics is currently developing an adeno-associated virus (AAV) vector-based gene therapy for the disease, isaralgagene civaparvovec (ST-920), which is intended to address needs that remain unmet with the currently available standards of care, which include enzyme replacement therapy and an oral medication.

Robert J. Hopkin, MD, an associate professor of clinical pediatrics at Cincinnati Children's Hospital Medical Center, recently presented data from the phase 1/2 STAAR clinical trial (NCT04046224), which is evaluating the safety and tolerability of ST-920 in 48 individuals in open-label, dose-ranging fashion, at the WORLDSymposium 2023, held February 22-26, in Orlando, Florida.

In an interview with CGTLive, Hopkin discussed preliminary findings from the STAAR trial, pointing out that supraphysiological levels of a-Gal A were seen in all the treated patients. He also spoke about safety, noting that none of the patients required prolonged hospitalization, intensive monitoring, or medications to suppress inflammation against a-Gal A or the AAV vector. In addition, Hopkin discussed preliminary findings from kidney biopsies, the potential implications for patients if ST-920 is approved, and future plans for further research for the gene therapy.