Mogenry (sonpiretigene isteparvovec)

Retinitis pigmentosa is a group of inherited diseases in which the retina's light-sensing cells, the rods and then the cones, break down over time^[15]. Rods handle vision in low light and cones handle bright light and color, so night vision usually goes first, side vision then narrows into tunnel vision, and central vision is affected later^[15]. Changes in more than 130 genes can cause it^[15].

Gene replacement, the approach behind Luxturna, needs viable retinal cells and a known gene, and Luxturna is limited to people with RPE65 changes in both gene copies who still have enough viable retinal cells^[14]. Mogenry takes a different route, called optogenetics. A harmless carrier virus, adeno-associated virus type 2 (AAV2), carries the gene for a light-sensing protein called a multi-characteristic opsin into bipolar cells, the retinal cells that normally pass signals on from rods and cones^[6][1].

Optogenetics aims to make these remaining retinal cells sensitive to light once rods and cones are lost, and Nanoscope's researchers chose bipolar cells because they are more plentiful than the retina's output cells and respond to ordinary room light once they carry the opsin^[11][13].

Nanoscope's researchers describe the opsin as built from 3 altered non-mammal proteins so that it responds to a broad range of light colors^[13]. Because Mogenry does not replace a faulty gene, Nanoscope says it needs no genetic testing to choose who gets it^[1]. Who qualifies for an approved use would be set by the FDA label.

RESTORE (NCT04945772) was a randomized, sham-controlled, double-masked trial in adults with advanced retinitis pigmentosa^[6]. ClinicalTrials.gov lists it as Phase 2, with a title calling it Phase 2b, while Nanoscope calls it Phase 2b/3^[6][1]. To join, the treated eye had to see worse than 1.9 LogMAR, about 20/1600, and the other eye no better than 20/800^[6].

Nanoscope randomized 28 people, and 27 were analyzed: 9 got the high dose, 9 the low dose and 9 a sham injection^[5]. The 6 listed sites were in California, Florida, North Dakota, Texas and Puerto Rico, and the trial ran from July 2021 to January 2024^[6].

Nanoscope said these endpoint analyses followed a revised analysis plan that it finalized after regulatory discussions and submitted to regulators before week 76, as announced on January 18, 2024^[5]. In a 2025 review, ICER noted that the evidence came from a 27-person trial, had not been peer reviewed at the time, varied a good deal between outcome measures and covered only 1 treated eye; 10 of the 12 members of its New England advisory council still voted that the evidence showed a net health benefit over usual care^[12].

Most RESTORE participants moved into REMAIN (NCT06162585), a long-term follow-up study with no new treatment that is active and no longer recruiting^[7][1]. Nanoscope said on September 15, 2026 that it would present 4-year REMAIN data at the Retina Society meeting on September 23, 2026, and that patients continue to maintain visual acuity gains, without giving figures^[4]. An earlier Phase 1/2a dose-finding study in India (NCT04919473) enrolled 11 people with advanced retinitis pigmentosa^[8].

Mogenry has also been tested in Stargardt disease. STARLIGHT (NCT05417126), an open-label Phase 2 study of 6 adults, reported an average gain of 5.5 letters on the eye chart at 48 weeks, with wide variation between people^[11][9]. Nanoscope said on November 5, 2026 that it plans a Phase 3 Stargardt trial in the near future, and none is listed on ClinicalTrials.gov^[3].

Mogenry has no FDA label, so its official side effects and warnings are not set. In RESTORE, Nanoscope reported that the therapy was generally well tolerated with no treatment-related serious or severe side effects^[5]. The most common side effects were mild or moderate anterior chamber cell, meaning inflammatory cells floating in the front of the eye, and ocular hypertension, meaning raised pressure inside the eye^[5].

Nanoscope reported no cases of endophthalmitis (infection inside the eye), retinitis or retinal vasculitis in the treated groups^[5]. In the smaller STARLIGHT study in Stargardt disease, all 6 treated people had at least 1 eye side effect, most often bleeding on the white of the eye, raised eye pressure and cells in the gel inside the eye, and none had retinal detachment or lost the eye^[11]. ICER, a drug value research group, wrote in 2025 that longer-term safety is uncertain because follow-up has been short^[12].

Nanoscope's first study of the therapy, then called vMCO-I, was a Phase 1/2a dose-finding study in India that began in October 2019^[8]. RESTORE began in July 2021^[6], and Nanoscope announced on March 26, 2024 that it met its main and key secondary goals^[5]. A Phase 2 Stargardt study, STARLIGHT, was published in EClinicalMedicine in August 2025^[11].

Nanoscope said on September 9, 2026 that the FDA had accepted and filed its Biologics License Application for retinitis pigmentosa with severe vision loss^[1]. The FDA has granted the therapy Fast Track and Orphan Drug designations for retinitis pigmentosa and Stargardt disease, and Regenerative Medicine Advanced Therapy (RMAT) designation for Stargardt disease, according to Nanoscope^[1].

On October 1, 2026 Nanoscope said Japan's regulator, the PMDA, had accepted its application for inherited retinal dystrophies with priority review, and that it expects potential approvals in both Japan and the US in the first half of 2027^[2]. Nanoscope's November 5, 2026 release still described the application as accepted and filed, with no FDA decision announced^[3].