Opus Genetics Reports Promising Early Results from BEST1 Gene Therapy Trial
Research News
First patient shows vision improvements with a good safety profile.
Opus Genetics announced encouraging initial clinical data from its Phase 1/2 trial of OPGx-BEST1, an investigational gene therapy for BEST1-associated retinal diseases. The first patient treated in the study showed improvements in both vision function and retinal structure at three months, with no safety concerns.
The patient, a 63-year-old woman with autosomal recessive bestrophinopathy (ARB) and severe functional impairment, experienced a gain in visual acuity equivalent to reading approximately two additional lines on an eye chart. This patient also experienced significant reduction in central retinal thickness and the subretinal fluid — a hallmark of BEST1 disease.
Importantly, the gene therapy was well tolerated with no eye inflammation, treatment-related side effects, or dose-limiting toxicities at the three-month mark.
BEST1-associated retinal diseases, including Best vitelliform macular dystrophy (BVMD) and autosomal recessive bestrophinopathy (ARB), are rare inherited conditions that cause progressive vision loss over time. These diseases affect thousands of patients worldwide and currently have no approved treatments available.
OPGx-BEST1 works by delivering a functional copy of the BEST1 gene directly to retinal pigment epithelium cells, where the defective gene is normally present. By restoring BEST1 protein function, the therapy aims to address the underlying genetic cause of retinal degeneration and preserve visual function.
The ongoing multicenter trial is evaluating the safety and effectiveness of a single subretinal injection across two dose levels. Two participants have been enrolled to date, with results from the full first cohort expected in mid-2026. Additional clinical sites are planned to open so that the company can expand patient access to this promising therapy.
"The preliminary results from this study, including the early favorable safety profile and initial signals of functional and structural improvement, are encouraging," said Dr. Mark Pennesi, study investigator at the Retina Foundation of the Southwest.
Opus Genetics is supported through the venture arm of the Foundation, the RD Fund, which invests in emerging therapies, including clinical proof of concept trials. The Foundation also provided research grant funding for the early preclinical development of OPGx-BEST1.
