EA-2353 from Endogena Therapeutics
Meanwhile, Endogena Therapeutics is also exploring an innovative approach that could have broad applicability. They have developed a drug that can potentially activate retinal stem and progenitor cells lying dormant in the eye. These cells could then develop into mature photoreceptors to support some restoration of vision.
The treatment, currently called EA-2353, is at the first stage of clinical testing, which will primarily establish its safety and tolerability. This study involves 14 people with RP in the USA, who are receiving the drug via injection into the eyeball. Early data suggests there are no serious side effects, so Endogena will now also start to make preliminary assessments of efficacy.
Transcorneal electrical stimulation from OkuVision
Another approach that could be appropriate for a large proportion of the Retina UK community is transcorneal electrical stimulation, which involves a device rather than a drug, and relies on the theory that electrical stimulation may induce a neuroprotective effect on retinal cells. This is being explored by German company OkuVision; their OkuStim device includes electrodes that are placed on the lower eyelid in contact with the eyeball, and can be used at home, in weekly 30-minute stints, after training from an ophthalmologist.
OkuStim was trialled several years ago at University Eye Hospital Tubingen (Germany) in around 50 people with RP, demonstrating good safety and tolerability. The results of that study have recently been reanalysed, and suggest that OkuStim can slow visual field loss, with the size of the effect correlating with the amplitude of the current used. OkuStim is currently undergoing a much larger trial within the German public health service, and this study should provide definitive evidence, within the next couple of years, as to whether the treatment can have a significant effect. If so, OkuVision hopes to persuade the NHS to make OkuStim widely available in the UK.
OkuStim is not the same as Fedorov Restoration Therapy – listen to our recent podcast on unproven treatments to find out more: