Positive Phase 3 Results Announced for Brimochol PF
Brimochol PF (Visus Therapeutics) is a preservative-free, fixed-dose combination of carbachol 2.75% and brimonidine tartrate 0.1%. In its first Phase 3 study (BRIO-I), the presbyopia-correcting drop was tested against 2 active comparators, brimonidine monotherapy and carbachol monotherapy. It successfully outperformed both, passing the important “contribution of elements” test required by the U.S. Food and Drug Administration (FDA).
Brimochol PF met the primary endpoint established by the FDA for presbyopia-correcting drops: A gain from baseline of at least 3 lines (15 letters) of binocular mesopic uncorrected near visual acuity, with less than a 1-line (5 letter) loss in binocular uncorrected distance acuity. The 3-line gain was achieved at 1, 2, 4, and 6 hours after a single dose of the topical medication—again, with no loss of distance vision. The fixed-dose combination also met prespecified EU and UK primary endpoints from 0.5 to 8 hours duration (carbachol P = 0.003; brimonidine P = 0.001) and out to 10 hours (carbachol P = 0.004; brimonidine P = 0.001). Almost 50% of participants continued to show an improvement of 2 lines of near distance vision at 10 hours. Participants in the study said they found the Brimochol PF duration of effect to be “just right.”
When investigators conducted objective measurements of pupil size, they found a statistically significant reduction in pupil size for Brimochol PF compared to active controls at all time points out to 10 hours, with the miotic effect gradually diminishing by the end of the day.
No loss of distance vision was observed in any of the 3 study arms. Rather, participants experienced a small, 2-letter gain in distance vision. There were no treatment-related serious adverse events and no adverse event-related discontinuations in the study. Headache was reported by less than 10% of subjects, and transient irritation on instillation by 14%. No hyperemia was reported in the Brimochol PF treatment group.
The study was a crossover design in which each participant received each of the 3 drugs for a single day, and visual acuity and pupil size were measured repeatedly throughout the day. In all, 182 emmetropic patients between the ages of 45 and 80 years were enrolled at 15 U.S. sites. A second Phase 3 study comparing Brimochol PF to a vehicle control is underway.
Figure: Pupil miosis effect in BRIO-1 study