News|Articles|October 28, 2026

OCT-980 receives FDA orphan drug designation for retinitis pigmentosa

Key Takeaways

The FDA granted orphan drug designation to OCT-980, Octant’s oral small molecule corrector, for retinitis pigmentosa, including RHO-adRP.
OCT-980 targets misfolded rhodopsin, aiming to restore its trafficking within photoreceptors in RHO-adRP.
The phase 1a healthy volunteer portion is complete, and an open-label phase 1b/2 study is enrolling patients at US sites.
No clinical safety or efficacy data have been reported, and primary completion is estimated for November 2028.
Byron L. Lam, MD said an oral corrector could complement gene-based approaches, but additive benefit and long-term safety need demonstrating.

FDA grants orphan drug designation to oral OCT-980 for RHO-adRP, now in phase 1b/2 testing at US sites.

The FDA granted orphan drug designation to OCT-980, an investigational oral small molecule corrector from Octant, for the treatment of retinitis pigmentosa, according to a company announcement. The designation covers rhodopsin-associated autosomal dominant retinitis pigmentosa (RHO-adRP), the indication under evaluation in an ongoing phase 1/2 trial.¹

OCT-980 is designed to correct misfolded rhodopsin and restore its trafficking within photoreceptors, targeting the mechanism behind many disease-associated RHO variants. The orphan status follows Octant's move into the clinic in March 2026, when the company dosed the first healthy volunteer in the program.^1,4 No therapy is currently approved for RHO-adRP.²

The first-in-human phase 1/2 study (NCT07408232) runs in two sequential parts. The phase 1a portion was a randomized, double-masked, placebo-controlled single ascending dose study with a food-effect cohort. It enrolled healthy volunteers in Australia and has concluded, according to the trial registry.²

The phase 1b/2 portion is an open-label, multicenter, multiple ascending dose study enrolling adults aged 18 to 65 years with genetically confirmed RHO-adRP at US sites. Participants receive oral OCT-980 tablets for up to 48 weeks, and eligibility requires best-corrected visual acuity above 70 ETDRS letters. The protocol excludes patients with any prior ocular surgery or any prior or current ophthalmic gene therapy.²

Safety and tolerability serve as the primary end point, assessed through day 5 in phase 1a and through week 60 in phase 1b/2. Secondary objectives include pharmacokinetics, pharmacodynamics, and efficacy, with an estimated primary completion date of November 2028. Octant has not reported clinical data from either portion.²

Beyond safety and tolerability, important functional measures include best-corrected visual acuity, low-luminance visual acuity, and microperimetry to detect efficacy,” Byron L. Lam, MD, professor of ophthalmology at Bascom Palmer Eye Institute, University of Miami Miller School of Medicine, told Modern Retina. Lam also pointed to OCT and fundus autofluorescence for assessing retinal preservation and monitoring structural changes.

What does orphan drug designation mean for OCT-980?

The FDA grants orphan drug designation to therapies for rare diseases, and the designation carries development incentives, including potential tax credits for qualified clinical trials and exemption from certain FDA application fees. If approved, OCT-980 would be eligible for 7 years of US market exclusivity, subject to applicable requirements. The designated indication spans retinitis pigmentosa broadly and includes RHO-adRP, the population enrolled in the current study.¹

The designation does not shorten or otherwise alter FDA review. Octant has not disclosed safety or tolerability findings from the completed phase 1a cohort, and no ocular adverse event data are available for OCT-980 at this stage.

The corrector strategy draws on a growing functional map of rhodopsin variants. A July 2026 study in Science Advances profiled all 6,612 possible RHO missense variants and identified more than 700 with pathogenic trafficking scores. In the same work, the small molecule corrector YC-001 restored surface trafficking in most mistrafficking variants, an approach relevant to the OCT-980 mechanism.³

Lam noted genetic testing is important for confirming a pathogenic or likely pathogenic RHO variant and determining whether the variant causes protein misfolding and impaired trafficking. “RHO Class II variants are particularly relevant mechanistically, but this classification alone does not establish responsiveness to a particular corrector,” he said.

“People with RHO-adRP are living with progressive vision loss and no approved treatment options today," said Sri Kosuri, PhD, co-founder and chief executive officer of Octant, in the announcement. "With our Phase 1b/2 study underway at US sites, we are focused on generating the clinical data needed to establish OCT-980 as an oral, disease-modifying option for RHO-adRP.”¹

An oral agent could complement gene-based and intraocular approaches in development, although additive benefit would need to be demonstrated, according to Lam. “Oral administration would avoid surgery and injection-related risks, and its overall benefit would depend on sustained efficacy and a favorable long-term systemic and ocular safety profile,” he said.

OCT-980 differs from most retinitis pigmentosa programs in late-stage development, which rely on ocular administration. These include the optogenetic therapy sonpiretigene isteparvovec (MCO-010; Nanoscope Therapeutics), now under BLA review. They also include laruparetigene zovaparvovec (laru-zova; Beacon Therapeutics), which met its primary end point in the pivotal VISTA trial in X-linked retinitis pigmentosa.

Earlier-stage activity also continues, with NouvSight001 recently cleared to enter retinitis pigmentosa clinical trials in the US and China. Results from the phase 1b/2 cohort will provide the first OCT-980 safety and efficacy data in patients with RHO-adRP.

Frequently Asked Questions

What is OCT-980?

OCT-980 is an investigational oral small molecule from Octant. It is designed to correct misfolded rhodopsin and restore its trafficking in RHO-adRP.

What does orphan drug designation provide for OCT-980?

The designation offers potential tax credits for qualified clinical trials and exemption from certain FDA fees. It also makes OCT-980 eligible for 7 years of US market exclusivity after approval.

What is the status of the OCT-980 phase 1/2 trial?

The healthy volunteer phase 1a portion is complete. The open-label phase 1b/2 portion is enrolling adults with RHO-adRP at US sites, with primary completion estimated for November 2028.