Ocugen completes enrollment in liMeliGhT phase 3 trial of OCU400 for retinitis pigmentosa

Ocugen has completed enrollment in liMeliGhT, its phase 3 clinical trial of OCU400 for the treatment of retinitis pigmentosa (RP). The company describes liMeliGhT as a 1-year clinical trial that will support the Biologics License Application (BLA) filing for OCU400 and potential approval in 2027.

OCU400 is a modifier gene therapy candidate based on a nuclear hormone receptor gene called NR2E3. According to the company, this gene regulates diverse physiological functions within the retina, such as photoreceptor development and maintenance, metabolism, phototransduction, inflammation, and cell survival. OCU400 is designed to reset this network to reestablish a healthy cellular homeostasis.

The trial enrolled 140 patients who were randomized 2:1 into the OCU400 arm or the untreated control group across mutations (RHO and gene-agnostic arms). The target population for the trial included patients with early- to late-stage disease among a broad RP population, including pediatrics (3+ years), according to the company. The primary endpoint of the trial is the 12-month change in visual function assessed by LDNA (luminance-dependent navigation assessment) with improvement in Lux Level from baseline to 12 months.

Victor H Gonzalez, Valley Retina Institute, McAllen, Texas, faculty at the University of Texas Rio Grande Valley, and the primary investigator for the liMeliGhT clinical trial, commented, saying, “It is critical to work towards FDA-approved treatment options that address the significant gap that remains for the approximately 98% of people living with RP who are not candidates for the approved gene therapy for RP. I am enthusiastic about the possibility of offering my patients with RP a safe, effective, and durable treatment option that could potentially stabilize vision loss or improve vision.”

The company also noted that positive long-term, 3-year phase 1/2 data for OCU400 was recently assessed in evaluable patients. OCU400 maintained a favorable durability, safety, and tolerability profile, with no new treatment-related serious adverse events or adverse events of interest emerging. Additionally, visual function benefits were consistently observed over 3 years, with 88% (7/8) of evaluable treated patients showing improvement or preservation versus untreated fellow eyes. An approximate 2-line gain (n=8) was also observed across multiple mutation types in treated eyes compared to untreated eyes at 3 years.

In 2026, Ocugen has also released positive preliminary 12-month data from its phase 2 ArMaDa trial evaluating OCU410 (AAV5-RORA) for the treatment of geographic atrophy secondary to dry age-related macular degeneration and positive results from its phase 1 GARDian1 trial of OCU410ST, a gene therapy for Stargardt disease.

Results from the ArMaDa trial² showed a 46% lesion growth reduction at 12 months (medium + high dose vs control; P = .015; n=23). Those treated with a medium dose (P = .02; n=10) achieved 54% lesion reduction compared with the control group, while those in the higher dose (P = .05; n=8) achieved 36% lesion reduction compared with the control group. Additionally, a subgroup of patients with ≥7.5 mm² at baseline (n=14) showed a 57% greater reduction in lesion size when compared with the control group.

While results from the phase 1 GARDian trial³ showed that among 6 patients with gradable fundus autofluorescence images, atrophic lesion growth was reduced by 54% (0.55 ± 0.27 mm²) in treated eyes, compared to untreated fellow eyes (1.19 ± 0.31 mm²) over 12 months​.

Ocugen plans to file the rolling BLA for OCU400 in the third quarter of 2026.

References:

1. Ocugen Announces Phase 3 liMeliGhT Enrollment Completion for OCU400, a Novel Modifier Gene Therapy for Broad Retinitis Pigmentosa. Published March 2, 2026. Accessed March 2, 2026. https://ir.ocugen.com/news-releases/news-release-details/ocugen-announces-phase-3-limelight-enrollment-completion-ocu400

2. Harp MD. Ocugen releases positive preliminary 12-month data from phase 2 ArMaDa trial. Published January 15, 2026. Accessed March 2, 2026. https://www.ophthalmologytimes.com/view/ocugen-releases-positive-preliminary-12-month-data-from-phase-2-armada-trial

3. Harp MD. Ocugen publishes phase 1 GARDian1 gene therapy data for Stargardt disease. Published January 13, 2026. Accessed March 2, 2026. https://www.ophthalmologytimes.com/view/ocugen-publishes-phase-1-gardian1-gene-therapy-data-for-stargardt-disease