PulseSight Therapeutics has unveiled positive phase 1 results for PST‑611, its non‑viral gene therapy candidate for dry age‑related macular degeneration (AMD) with geographic atrophy (GA), following a podium presentation at ARVO 2026.
The first‑in‑human study, PST‑611‑CT1, assessed two ascending dose levels of PST‑611 in six patients across Paris and Grenoble, with a 16‑week follow‑up. Investigators reported that the trial met its primary and secondary objectives, with the therapy demonstrating excellent safety and tolerability.
Most ocular adverse events were mild, two were moderate and no intraocular inflammation, treatment‑emergent serious adverse events or suspected unexpected serious adverse reactions were observed. Best corrected visual acuity remained stable throughout.
Although not designed to measure efficacy, the study generated encouraging early signals. Patients spontaneously reported functional improvements in vision, while anatomical assessments suggested inflections in GA lesion growth. In one participant, the effect persisted beyond the trial’s follow‑up period.
Presenting the findings, Professor Francine Behar‑Cohen said: “Geographic atrophy is a progressive, sight‑threatening disease with no effective treatment currently available in Europe— the unmet medical need is real and urgent.
“These Phase 1 results are therefore particularly meaningful. PST‑611 demonstrated excellent tolerability, which is fundamental when treating patients with a chronic condition. What makes these results stand out are the early efficacy signals we observed, both anatomically and functionally. I look forward to the Phase 2a trial, which will allow us to confirm the therapeutic potential of PST-611 over a longer follow-up and in a larger group of patients.”
Judith Greciet, PulseSight’s chief executive officer, said: “We are thrilled by the outcome of our first-in-human study of PST-611. The trial met its primary objective with an excellent safety profile and went beyond our expectations: we observed early functional and anatomical efficacy signals, notably spontaneous reports from several participants of noteworthy vision improvements, after a single dose and just four months of follow-up.”
PulseSight has submitted a clinical trial authorisation application in France for a repeat‑dose phase 2a study evaluating three administrations of PST‑611 in up to 20 patients. Pending approval, the trial is expected to begin in the second half of 2026, with results anticipated in 2028.
