Opus Genetics reports sustained LCA5 vision gains at 24 months
Opus Genetics has presented interim clinical data from its OPGx-LCA5 and OPGx-BEST1 gene therapy programmes at the Retina in Rio 2026 conference in Brazil, reporting sustained improvements in visual function across both rare inherited retinal disease (IRD) indications.
The Nasdaq-listed company said OPGx-LCA5, its AAV8-based candidate targeting Leber congenital amaurosis type 5 (LCA5), demonstrated maintained gains in visual acuity and light sensitivity in three adult participants out to 24 months following treatment. Three adolescent participants showed restoration of cone-mediated vision with sensitivity improvements reaching normal ranges through six months of follow-up. All participants in the cohort received the low dose of 1E10 vector genomes per eye. Notably, participants reported meaningful functional gains in daily life, including recognising family members, navigating independently, and identifying objects and colours that had previously been inaccessible to them.
OPGx-BEST1 early signals
Data from the low-dose Cohort 1 of the Phase 1/2 BIRD-1 trial of OPGx-BEST1 showed improved retinal sensitivity in three of four evaluable participants, a 75% response rate, measured using microperimetry in the transitional zone surrounding damaged retinal tissue. The company said accompanying analyses linked optical coherence tomography (OCT) imaging characteristics to treatment response, which it intends to use to refine participant selection and measurement strategies in subsequent cohorts. High-dose Cohort 2 of the BIRD-1 trial has now completed enrolment with 11 participants, and data from that cohort will be a critical next catalyst for the programme.
George Magrath, chief executive of Opus Genetics, said the findings "strengthen our understanding of how to measure treatment response in IRDs and support the continued advancement of both programs."
Phase 3 on the horizon
Based on the Phase 1/2 LCA5 dataset, Opus advanced OPGx-LCA5 directly into Phase 3 development at the low dose without further escalation. The Phase 3 trial's natural history and treatment cohorts are fully enrolled, with dosing initiation targeted for the fourth quarter of 2026. The primary efficacy endpoint will assess improvements in retinal sensitivity across 16 central retinal test locations, a more granular measure than conventional letter-chart acuity tests.
The inherited retinal disease space has attracted sustained interest from both large pharmaceutical companies and specialist gene therapy developers. Spark Therapeutics' Luxturna (voretigene neparvovec), approved by the FDA in 2017 for RPE65-associated IRD, established the regulatory and reimbursement template for this category, demonstrating that durable single-administration gene therapies can achieve approval and meaningful pricing. Subsequent programmes from companies including REGENXBIO, Applied Genetic Technologies and Beacon Therapeutics have explored multiple IRD targets including RPGR, CNGB3 and BEST1, reflecting the broader bet that AAV-mediated subretinal delivery can be adapted across genetically diverse patient populations. Opus's pipeline of seven AAV programmes positions it as one of the more diversified pure-play IRD developers.
Key uncertainties remain. The LCA5 Phase 1/2 cohort that underpins the Phase 3 advance is small, comprising six participants at a single dose level, and 24-month adult data have not yet been presented in a peer-reviewed setting. The BEST1 programme is at an earlier stage with shorter follow-up. Investors and clinicians will look for Cohort 2 BEST1 data and the first Phase 3 LCA5 dosing readout as the near-term milestones that substantiate the current trajectory.