AAVantgarde shares Usher syndrome and Stargardt disease data at EURetina 2026

AAVantgarde Bio presented clinical and preclinical data for two of its genetic medicine programs on October 4, 2026, at the 26th European Society of Retina Specialists Annual Congress in Vienna. The clinical-stage biotechnology company shared updates on its Phase 1/2 trials targeting rare inherited retinal diseases that currently lack approved treatments.

Clinical Findings from the LUCE-1 Trial in Usher Syndrome Type 1B

Prof. Francesca Simonelli delivered preliminary findings from the LUCE-1 Phase 1/2 study, which evaluates subretinal administration of AAVB-081 in adults with Usher type B retinitis pigmentosa. Enrollment in the open-label trial concluded in January 2026 with 15 participants treated across three dose cohorts. As of the August 3, 2026 data cutoff, investigators recorded no serious adverse events, dose-limiting toxicities, or study discontinuations. Ocular inflammation remained limited, matched expectations, and responded to corticosteroid treatment.

Among 12 participants in the low- and mid-dose cohorts with at least six months of follow-up, researchers observed early signs of visual function improvement. Seven individuals achieved at least a one-line improvement in best-corrected visual acuity, including four who gained two lines or more. Six participants reached at least a one-line improvement in low-luminance visual acuity, with four showing an improvement of three lines or more. Exploratory tests also indicated supportive signals in fixation stability and microperimetry.

Preclinical Data and Vector Design for Stargardt Disease

Prof. Paulo Eduardo Stanga presented new preclinical and translational data for AAVB-039, a dual AAV8.ABCA4 gene therapy designed for STGD1. AAVB-039 utilizes a dual AAV intein-mediated protein trans-splicing approach to deliver the full-length gene to photoreceptors.

Testing across mouse, pig, and non-human primate models showed successful reconstitution of full-length ABCA4 proteins alongside reduced lipofuscin accumulation and a favorable ocular safety profile. In a STGD1 pig model, treatment drove full-length ABCA4 expression past 100 percent of endogenous levels while lowering lipofuscin accumulation compared to sham-injected knockout eyes. In non-human primates, 76 to 99 percent of photoreceptors showed co-transduction across approximately 60 percent of the analyzed retinal section. Ocular effects appeared mild and transient, with temporary, dose-related changes on electroretinography and minimal histological findings that improved over time.

AAVB-039 Clinical Trials Recruit Patients Across Several Regions

The clinical development framework for AAVB-039 encompasses the STELLA natural history study, which has finished enrolling 150 patients, alongside the CELESTE first-in-human Phase 1/2 trial. CELESTE is actively recruiting participants with STGD1 driven by biallelic pathogenic ABCA4 variants across trial sites in the United States, the United Kingdom, and Europe.

The data presented at EURetina 2026 provide important updates across both of our lead programs. In LUCE-1, the continued absence of serious adverse events or dose-limiting toxicities, together with early signals of improved visual function in the low- and mid-dose cohorts, support the continued development of AAVB-081 in Usher syndrome type 1B. At the same time, the preclinical data for AAVB-039 demonstrate consistent ABCA4 expression, lipofuscin reduction and favourable ocular safety across relevant large animal models, supporting the ongoing clinical translation of our dual AAV intein platform in Stargardt disease.

Dr. Jayashree Sahni