Bota-vec for XLRP

X-linked Retinitis Pigmentosa (XLRP)

X-Linked Retinitis Pigmentosa

Retinitis pigmentosa refers to a group of inherited retinal diseases (IRDs) that represent the most common genetic cause of blindness (Genetics Home Reference 2019). One of the most severe forms of retinitis pigmentosa is X-linked (XLRP) which makes up 8%-16% of all RP. Approximately 80% of XLRP results from variants in the retinitis pigmentosa GTPase regulator (RPGR) gene.

XLRP caused by RPGR mutations is a severe, degenerative disease of the retina. Onset is early and progression is rapid. Symptoms present in childhood initially as loss of night vision which continues to “tunnel vision” during young adulthood with progressive retinal degeneration resulting in loss of central vision and complete blindness generally during the 3rd or 4th decade of life.

XLRP affects men and women differently, with men more likely to experience severe symptoms.

It is estimated that there are over 20,000 XLRP patients in the U.S. and Europe.

In patients who still have some residual sight, the current mainstay of treatment is supportive care, confined to correction of refractive error with the use of low-vision aids and access to educational and work-related opportunities (Hamel 2006, Sahni 2011) which provide limited benefits and has no impact on retinal degeneration and disease progression.

There are currently no approved treatments available for RPGR-XLRP that effectively impact the inexorable progressive decline in vision that these patients experience, resulting in a substantial unmet medical need.

About Bota-vec (AAV-RPGR)

Bota-vec (AAV-RPGR) is a gene therapy designed to replace the RPGR gene function missing in RPGR-XLRP patients which is delivered to patients via a one-time subretinal injection into each of their eyes.

Bota-vec has been studied in three clinical studies to date. These included a Phase 1/2 study with a dose escalation phase in which each participant was treated in one eye (unilateral) and the untreated fellow eye in each individual was used as the control. Following the dose escalation phase, this unilateral Phase 1/2 study was expanded into a randomized expansion arm in which the treated eye in participants receiving bota-vec was compared to a randomized untreated single eye in participants randomized to the control group in which treatment was deferred for 6 months.

Results from the Phase 1/2 study showed improvements in bota-vec treated eyes compared to randomized unilateral control eyes in endpoints reflecting each of the domains of vision: functional vision, and visual function.

Safety and efficacy data from the Phase 1/2 study (n=46) supported the initiation of a randomized, controlled global Phase 3 study of bilateral treatment with bota-vec (in both eyes). A total of 95 participants enrolled in the LUMEOS Phase 3 study in which bilateral treatment with bota-vec gene therapy was compared to an untreated control group in which treatment was deferred for 12 months. Benefit was demonstrated in every domain of vision in bota-vec treated patients compared to untreated controls (each with nominal significance). Safety profile of bota-vec was favorable with no new safety signals noted in the bilateral phase 3 study compared to earlier unilateral studies.

Based on the data demonstrating the benefit and safety of bilateral treatment with bota-vec, MeiraGTx is filing for regulatory approval of bota-vec globally.

Bota-vec Corporate Presentation April 16, 2026

In June 2025, the Foundation for Fighting Blindness published a public letter signed by 30 leading retinal specialists voicing their support for approval of bota-vec based on “life changing improvements after treatment in the Phase 3 LUMEOS trial”.

See a copy of the FFB letter here:
Retinal Research Community Urges Johnson & Johnson to Seek Regulatory Approval for its XLRP Gene Therapy