Paris, France, October 7, 2026 – PulseSight Therapeutics SAS, an ophthalmology clinical-stage biotech company developing disruptive non-viral vectorized gene therapies with minimally invasive delivery technology, has presented further data from its PST-611 phase I clinical trial (CT1) in patients with advanced dry age-related macular degeneration (AMD), known as geographic atrophy (GA), in an oral presentation at the European Society of Retina Specialists’ 26th Euretina Congress, held 1-4 October 2026 in Vienna1.
AMD is the leading cause of central vision loss in the elderly, affecting 200 million people worldwide, and GA remains a high unmet need as no treatments are approved in Europe for this condition.
The CT1 phase I trial was a first-in-human study aimed at evaluating the safety and tolerability of a single PST-611 administration. A total of six patients with advanced dry AMD/GA were treated with one dose of PST-611 in two successive cohorts at two escalating dose levels with a four-month follow-up. Previous results presented at ARVO in May 2026 demonstrated that PST-611-CT1 met the primary and secondary objectives, demonstrating excellent safety and tolerability at both dose levels.
Following spontaneous reports from study participants claiming a vision improvement after PST-611 administration and clinical observation of the OCTs showing a slowing of GA lesion growth dynamic, PulseSight performed a quantitative post hoc analysis using RetinAI Discovery® platform and AI models to quantify structural changes in four OCT biomarkers of retina cell loss, before and after the administration of PST-611. The data were presented at Euretina, showing positive early signals of efficacy in five out of six treated patients.
In the full study population, all biomarkers, measured over the four-month period after treatment versus before, presented a consistent mean reduction of their growth rate ranging from 35 to 52%, supporting PST-611’s ability to protect and preserve RPE and photoreceptors in GA patients. Specifically, the mean RPE depletion growth rate dropped by 40% over the four-month period compared to before, a remarkable effect size in such an early onset.
The spontaneous, yet specific reports by the study participants of vision improvement in their daily activities, associated with the reduction in photoreceptors’ specific markers (ellipsoid zone (EZ) depletion rate (35%) as well as EZ thickness loss rate (52%)), are positive signs that PST-611 could also have the potential to preserve visual function.
PST-611 is a first-in-class therapy candidate encoding transferrin that plays a key role in the control of iron homeostasis. Dry AMD/GA is associated with a dysregulation of iron levels and oversaturation of transferrin. Through the expression of transferrin, PST-611 intervenes in a key upstream mechanism of GA pathogenesis and, thus, targets the multiple downstream biological cascades that drive the disease progression.
Presenting the results, PulseSight’s CMO George Weissgerber, MD, said, “We are thrilled by the positive outcome of our first-in-human study of PST-611. The study data demonstrate the excellent safety profile of PST-611, which is fundamental for patients, and this post hoc quantitative OCT biomarker analysis shows very promising signals of efficacy. Indeed, the effect size, the consistency of the results in the responding eyes, the improvement in structural biomarkers as well as reports of functional improvements and the early onset of effect, lasting over four months after a single administration are remarkable. These are very valuable insights as we initiate our phase 2 trial, which aims to confirm the safety and efficacy profile of PST-611.”
Prof Francine Behar Cohen, inventor of PulseSight’s technology and principal investigator at the Department of Ophthalmology, Cochin – Assistance Publique-Hôpitaux de Paris (AP-HP), said, “The results from the study are very encouraging. It adds to the validation of PulseSight’s technology platform and supports the interest in targeting ferroptosis as a novel therapeutic approach in dry AMD and GA. PST-611 has shown an excellent safety profile and clear early efficacy signals in this first-in-human trial and I am very enthusiastic to be part of the next-stage clinical trials.”
Judith Greciet, PulseSight‘s CEO, added, “It is a very special moment for PulseSight, translating our research into human data and uncovering PST-611’s clinical profile. The CT1 study has confirmed the excellent safety profile and remarkable early efficacy signals. The long-lasting effect allows us to reduce treatments to 2-3 times a year, strongly improving patients’ compliance. We believe PST-611 has the potential to be a blockbuster, first-in-line treatment for GA, where a critical unmet patient need remains. We are eager to commence the phase IIa trial to further confirm these data in a larger cohort over a longer treatment period.”
The phase IIa trial (PST-611-CT2a) aims to assess PST-611’s safety and efficacy in up to 24 patients, after up to three administrations over 12 months. This trial is planned to start in H2 2026 with results available in 2028.
- Oral presentation: Session 6 #138, Presenter: George Weissgerber, MD, Title: Transferrin in geographic atrophy patients using non-viral ocular gene therapy: safety, tolerability and early efficacy results from PST-611-CT1, a first-in-human trial, Date: 2 October 2026. See Abstract.
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About Age-related Macular Degeneration (AMD)
AMD develops with aging. It is a disease with progressive, painless loss of central vision with a strong burden on patients’ everyday life, impacting their ability to read, recognize faces and see objects, and ultimately leading to irreversible central vision loss. Dry AMD is the most common form of AMD, progressing through successive stages into the late form of dry AMD, also called geographic atrophy (GA). Wet AMD is a less common type of late AMD causing faster vision loss. Any stage of dry AMD can turn into wet AMD. In all its forms, AMD represents a compelling unmet need for more effective and durable treatment options, with a large and growing market, estimated to reach $27.5 billion by 2031.
About PulseSight Therapeutics
PulseSight is a clinical-stage biotech company committed to developing disruptive non-viral vectorized therapies with minimally invasive delivery technology for the treatment of retinal disease with a focus on age-related macular degeneration (AMD) including wet AMD and geographic atrophy (GA) secondary to dry AMD.
PulseSight’s technology platform delivers DNA plasmids encoding therapeutic proteins into the ciliary muscle using an electro-transfection system. The ciliary muscle cells act as biofactories, expressing therapeutic proteins that reach the retina with high distribution, providing a safe and long-acting treatment for major eye diseases.
About PST-611 for GA
PST-611 encodes the human transferrin protein, a crucial regulator of iron homeostasis, and holds the potential to effectively address key pathological mechanisms in dry AMD/GA.
Dry AMD involves the dysregulation of iron homeostasis, resulting in an excess of free iron.
Iron is crucial for proper cell function; however, excess free iron is highly toxic, inducing a Fenton reaction at the mitochondrial level, responsible for multiple toxic pathways, oxidative stress, lipid peroxidation and inflammation, ultimately leading to ferroptosis, a well-established cell death mechanism.
Transferrin is an endogenous protein playing a central role in the regulation of iron homeostasis.
Thanks to the innovative delivery technology, PST-611 expresses transferrin, which reaches the retina and restores normal free:bound iron balance, preventing the toxic cascade initiation upstream.
PST-611 has been shown to protect photoreceptors and retinal pigment epithelium (RPE) cells from death and to preserve visual function in animal models.
PulseSight is based in Paris, France, and its investors are Pureos Bioventures, ND Capital and Korea Investment Partners (KIP).
For more information visit www.PulseSightTherapeutics.com
Watch the video of the technology here: www.PulseSightTherapeutics.com
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