Opus Genetics releases findings from Phase I/II trial of OPGx-BEST1 gene therapy

Opus Genetics has revealed early results from its Phase I/II trial of OPGx-BEST1 gene therapy, showing positive safety and visual improvements in patients with Best vitelliform macular dystrophy and autosomal-recessive bestrophinopathy, marking a promising step for retinal disease treatment.

Opus Genetics has shared early findings from its ongoing Phase I/II clinical trial of OPGx-BEST1, a gene therapy designed for the treatment of Best vitelliform macular dystrophy (BVMD) and autosomal-recessive bestrophinopathy (ARB). These preliminary results were presented at the 49th annual meeting of the Macula Society in San Diego, California, USA.

Study Overview and Participant Details

The early data presented includes details of a 63-year-old female participant diagnosed with ARB. The results sparked cautious optimism as the participant responded positively to OPGx-BEST1, indicating a promising outcome from this gentle therapy. This suggests not only a safe approach to treatment but also the potential for real progress in managing these retinal diseases.

Key Findings

Safety and Tolerability

After three months of treatment, OPGx-BEST1 demonstrated excellent safety and tolerability. No ocular inflammation, adverse events, or dose-limiting toxicities were reported, confirming that the therapy can be safely administered without significant side effects.

Visual Acuity Improvement

One of the most significant results was the improvement in the participant's best corrected visual acuity (BCVA). The treated eye showed a 12-letter gain in BCVA, indicating a functional improvement in vision, which is a promising sign for the potential effectiveness of the therapy in treating patients with BVMD and ARB.

Central Subfield Thickness

The study also noted a reduction of 23% in the central subfield thickness of the treated eye, reflecting a positive anatomical response to the treatment. This reduction in thickness is an important indicator of the therapy’s ability to impact the structural health of the retina.

Intraretinal Fluid Resolution

Another noteworthy result was the resolution of intraretinal fluid in the treated eye within just one month. The fluid disappeared in areas with minimal atrophy, suggesting that OPGx-BEST1 has potential not only for functional improvement but also for anatomical restoration of retinal tissue.

Trial Design and Objectives

The Phase I/II trial is an open-label, adaptive study in which each participant receives a single, targeted dose of OPGx-BEST1 directly beneath the retina in their affected eye. The goal of this study is to evaluate the safety and tolerability of OPGx-BEST1, refine the treatment dose for future patient trials, and track long-term outcomes focusing on both functional and anatomical endpoints.

The trial consists of two participant groups: one with BVMD and another with ARB. Both groups receive distinct treatment regimens, but the core aim of the study remains to gather data on the safety and effectiveness of OPGx-BEST1 as a therapeutic option for these diseases.

CEO's Statement

George Magrath, CEO of Opus Genetics, expressed optimism about the initial results, saying, "We are encouraged by the results from our first participant, which demonstrate that OPGx-BEST1 was well-tolerated and showed promising early efficacy after three months. While this data is still in its early stages, it represents a significant milestone for our OPGx-BEST1 program and for patients suffering from BEST1-related retinal diseases."

Magrath further emphasized the company's commitment to growth, stating, "We are expanding our presence across the country, increasing our team with new hires at our two existing US hubs, while preparing to open new offices in Cincinnati, Florida, and New York. Currently, two participants are enrolled in the study, and we expect to complete the first cohort by mid-2026, providing a more comprehensive understanding of the treatment’s impact."

Future Directions

Opus Genetics initiated the first wave of OPGx-BEST1 treatment in November 2025, carefully introducing the gene therapy to patients with Best disease as part of its Phase I/II trial. The company is hopeful that this early-stage research marks the beginning of a new era in the treatment of BVMD and ARB, both of which have long been challenging to manage with existing therapies.

As the company advances its gene therapy program, it is pushing toward a future where gene-based treatments can offer hope for restoring vision to patients affected by these retinal disorders. The promising results thus far provide an early glimpse into the potential for OPGx-BEST1 to change the treatment landscape for those suffering from Best disease and other related retinal conditions.

Sources:

• Opus Genetics releases findings from Phase I/II trial of OPGx-BEST1 gene therapy
• Opus Genetics reports promising early data from Phase I/II OPGx-BEST1 trial
• Opus Genetics shares early results from OPGx-BEST1 trial for retinal diseases
• Opus Genetics reports Phase I/II trial results of OPGx-BEST1 gene therapy