AAO 2026: MCO-010 sustains vision gains in RP through 4 years

A single intravitreal injection of the optogenetic therapy sonpiretigene isteparvovec (MCO-010; Nanoscope Therapeutics) produced visual acuity gains in patients with severe vision loss from retinitis pigmentosa (RP) that were sustained through 4 years, according to data presented by Kenneth C. Fan, MD, MBA, a vitreoretinal and inherited retinal disease specialist at Retina Consultants of Texas in Houston. Fan presented the 4-year REMAIN follow-up data from the phase 2b/3 RESTORE trial at the American Academy of Ophthalmology (AAO) 2026 Annual Meeting in New Orleans, Louisiana, and discussed them with Ophthalmology Times.¹

Patients with RP face “a very tragic, progressive vision loss,” Fan said, and no FDA-approved gene-agnostic therapy exists for them. MCO-010 is a disease-agnostic therapy that delivers a light-sensitive opsin protein to retinal bipolar cells. The bipolar cells can then serve as a proxy for lost photoreceptors, sending signals to the brain when light is present.

What did RESTORE and REMAIN show?

RESTORE randomly assigned 27 patients to a single injection of MCO-010 at 1 of 2 doses (1.2 × 10¹¹ or 0.9 × 10¹¹ gene copies per eye) or sham.¹ At week 52, mean best-corrected visual acuity (BCVA) improved from baseline by 0.337 logMAR in the high-dose group and 0.382 logMAR in the low-dose group (P = .02 and P = .03, respectively).¹ At week 204 of REMAIN, the long-term follow-up study, mean BCVA gains were 0.261 logMAR and 0.244 logMAR, respectively. That is equivalent to an approximately 3-line Early Treatment Diabetic Retinopathy Study improvement.¹ “Overall, I think still maintaining 13, 14 letters gained in the entire study cohort,” Fan said. No serious adverse events were reported, and the mild to moderate intraocular inflammation that occurred was treatable.¹

What do the data mean for patients with RP?

Current care for patients with RP relies on low vision rehabilitation and assistive devices, including emerging artificial intelligence–based tools such as cameras built into glasses. “If there truly is a way for optogenetics to improve vision that has already been lost, that gives a lot of hope to patients,” Fan said. The FDA has accepted Nanoscope’s Biologics License Application for MCO-010, and Fan said he is “really rooting for some sort of treatment that can be available for our patients.”

Related coverage:

• FDA accepts BLA for Mogenry in retinitis pigmentosa
• FAQ: What retina specialists need to know about the Mogenry (MCO-010) BLA acceptance
• Retina Society 2026: MCO-010 maintains visual acuity gains through 4 years in advanced RP
• ASRS 2026: MCO-010 sustains 3-line vision gains at 3 years

>>> For more from the meeting, visit Ophthalmology Times’ AAO 2026 coverage.

Reference
1. Fan KC. Lasting vision improvement in retinitis pigmentosa: REMAIN 4-year study data from the RESTORE phase 2b/3 trial of MCO-010 optogenetic therapy. Presented at: American Academy of Ophthalmology 2026 Annual Meeting; October 11, 2026; New Orleans, LA. Session PA044.