Opus Genetics Announces Positive Phase 1/2 Cohort 1 Data for OPGx-BEST1

What Happened

• On September 9, 2026 Opus Genetics (IRD) issued a press release and investor presentation reporting interim results from Cohort 1 (low dose) of its Phase 1/2 trial BIRD-1 of OPGx-BEST1 for BEST1-related retinal diseases (BVMD and ARB). Cohort 1 enrolled five participants treated at 1.5 x 10^9 vg/eye (three BVMD participants with 3-month follow-up; two ARB participants with 6-month follow-up). All five participants showed clinically meaningful improvements in visual function by one or more measures (BCVA, LLVA, contrast sensitivity or microperimetry). The treatment showed a favorable safety profile with no serious adverse events, no dose-limiting toxicities, and no intraocular inflammation reported.

Key Details

• Cohort 1 dosing: 1.5 x 10^9 vg/eye; 5 participants total (3 BVMD, 2 ARB).
• Functional outcomes: BCVA improved in 60% (3/5), LLVA improved in 40% (2/5), contrast sensitivity improved in 40% (2/5); microperimetry improvement in 75% (3/4) of evaluable participants.
• Structural outcomes: improvements in 4/5 participants; reductions in vitelliform material in 67% of BVMD (2/3) and reductions in intraretinal fluid in 100% of ARB (2/2).
• Next steps/timeline: Company advanced to higher-dose Cohort 2 at 4.5 x 10^9 vg/eye (over-enrolled to 8 participants). Dosing expected complete Q4 2026; topline 3-month Cohort 2 data expected Q2 2027. FDA meeting in Aug 2026: alignment on a potential pivotal endpoint (≥3 dB microperimetry improvement in ≥5 prespecified loci plus a patient-reported outcome); Phase 3 and commercial manufacturing requirements expected complete early 2027. New epidemiology: ~23,600 symptomatic BEST1 patients in U.S. (13,000 diagnosed; 10,600 undiagnosed) and ~45,400 globally.

Why It Matters

• For investors, these results represent a positive early proof-of-concept signal: measurable functional and structural improvements were reported with a clean short-term safety profile in a small cohort. Advancement to a higher-dose cohort and FDA alignment on potential pivotal endpoints clarify the regulatory and development pathway and set near-term milestones (Cohort 2 dosing completion Q4 2026; topline data Q2 2027).
• Caution: data are interim from a small number of patients and the company highlights typical forward-looking risks (results may change with more patients/follow-up). Investors should view these outcomes as preliminary while monitoring upcoming Cohort 2 and regulatory progress.