The US Food and Drug Administration (FDA) has granted fast track designation to Sanofi’s investigational gene therapy SAR446597 for geographic atrophy (GA). The therapy, designed for one-time intravitreal delivery, targets 2 key components of the complement cascade—C1s in the classical pathway and factor Bb in the alternative pathway.

Fast track designation is intended to expedite development and review of therapies for serious conditions with unmet medical need. Sanofi’s gene therapy delivers genetic material that encodes 2 therapeutic antibody fragments aimed at suppressing complement activity in the retina. By inhibiting both pathways, the therapy seeks to reduce retinal damage associated with GA while eliminating the need for repeated intravitreal injections.

Sanofi plans to begin a phase 1/2 clinical trial to assess the safety, tolerability, and efficacy of SAR446597. The company also has another gene therapy candidate, SAR402663, in early-stage clinical testing for patients with neovascular age-related macular degeneration. RP