Phase III trial of Rescula in retinitis pigmentosa fails to meet end point-R-Tech Ueno

R-Tech Ueno has announced the end of a Phase III clinical study with Rescula (unoprostone) ophthalmic solution for the treatment of retinitis pigmentosa. This multicenter study using a placebo as control was carried out in patients with visual field constriction and then deterioration of vision involving a double-masked controlled study for 52 weeks for efficacy, followed by the open trial study for a further 52 weeks for safety. The primary endpoint of the study was the changes in the value of the mean retinal sensitivity at four central points through HFA (10-2).

Results indicate that the difference compared to the placebo group was not statistically significant. However, the primary endpoint and visual acuity of unoprostone group demonstrated improvement compared to Day 0 (before the study) and the difference was statistically significant. In addition, the Goldmann visual field of the placebo group progressed statistically and significantly the constriction of the visual field compared to Day 0. Furthermore the total score of VFQ-25 was found to have improved statistically and significantly in the unoprostone group. The trial is now closed.

Comment: There are currently no drugs approved for the treatment of retinitis pigmentosa but a number are in early studies, including stem cell therapy ReN 003, from ReNeuron, and the recombinant growth factor OCU 100 from Ocugen.