Retinal Therapeutic Advancements: Xelafaslatide's Phase 1b Insights

Phase 1b results for xelafaslatide Phase 1b data show tolerability across evaluated intravitreal doses and an early, directional reduction in geographic atrophy (GA) lesion growth at six months—supporting a potential neuroprotective approach of interest to retinal specialists. The study reported no dose‑limiting toxicities and an adverse‑event profile consistent with intravitreal administration; preliminary structural and functional readouts favored treated eyes.

Safety findings were straightforward: single intravitreal doses from 50 µg to 200 µg were tested across an open‑label dose‑escalation cohort and randomized treatment cohorts, and investigators observed no dose‑limiting toxicities. Ocular and systemic adverse events aligned with expectations for intravitreal therapy, with tolerability supporting continued dose exploration under standard post‑injection monitoring for inflammation and visual changes.

Treated eyes demonstrated slowed GA lesion growth at six months compared with untreated controls, with most participants maintaining best‑corrected visual acuity. Xelafaslatide acts as a Fas inhibitor, blocking Fas‑mediated cell death and providing a plausible mechanism for the observed structural preservation and functional signals. The magnitude of effect was modest but directionally consistent across cohorts; these early efficacy signals require confirmation in larger, controlled trials.

The trial combined a multicenter, open‑label dose‑escalation phase (N=6) with randomized, double‑masked, sham‑controlled treatment cohorts (additional N=22), focusing on safety as the primary endpoint and GA lesion area plus BCVA as key secondary measures. Imaging‑based lesion measurements and standardized visual function testing supported interpretability, with primary readouts collected through 24 weeks to inform next‑phase design.