GenSight Biologics reports sustained visual acuity gain at 78 weeks in its Phase I/II Study with GS010 for the treatment of Leber’s Hereditary Optic Neuropathy (LHON) as well as confirmation of the good safety and tolerability profile of GS010 and sustained improvement of visual acuity in patients with vision loss for less than two years
GenSight Biologics a biopharma company that discovers and develops innovative gene therapies for neurodegenerative retinal diseases and diseases of the central nervous system, has reported additional promising results after 78 weeks of follow-up in its Phase I/II clinical trial. These results confirm the favourable safety and tolerability profile of GS010, while demonstrating sustainable visual acuity improvement in patients with Leber’s Hereditary Optic Neuropathy (LHON).
Each cohort of three patients was administered an increasing dose of GS010 through a single intravitreal injection in the eye most severely affected by LHON. Recruitment was completed in April 2015 and long-term follow-up is ongoing. These patients had an average onset of disease of 6 years at the time of treatment. At baseline, both treated and untreated eyes had an off-chart median visual acuity.
At 78 weeks post-injection, the mean change of visual acuity from baseline in the treated eyes of all patients was -0.61 LogMAR (p<0.001), equivalent to a mean improvement of +30 ETDRS letters. For all untreated eyes at week 78, the mean change from baseline was -0.31 LogMAR (p=0.0866), equivalent to a mean improvement of +15 ETDRS letters. This provides a treatment effect (mean difference between treated worse-seeing and untreated best-seeing eyes) of +15 letters (p=0.11) in favour of treated worse-seeing eyes.
More interestingly, in patients with an onset of vision loss of less than 2 years at the time of treatment, a mean gain of +32 ETDRS letters (-0.63 LogMAR) was observed in treated eyes, while a mean gain of +12 ETDRS letters (-0.23 LogMAR) was observed in untreated eyes, resulting in a difference of 20 ETDRS letters in favour of treated eyes.
The patient group with vision loss for 2 years or less at the time of injection demonstrated a treatment effect in favour of the treated eye of increasing magnitude from week 36 onward