The effect of MK-927, a topical carbonic anhydrase inhibitor, on IOP in glaucomatous monkeys

Abstract

MK-927 is a water soluble, potent inhibitor of human carbonic anhydrase (CA) II in vitro. Topical administration of MK-927 reduces intraocular pressure (IOP) in rabbits. Elevated IOP was produced in cynomolcjus monkey eyes by argon laser photocoagulation of the trabecular meshwork. IOP was measured at 0 hr, 0.5 hr and hourly for 8 hrs in 8 eyes for two baseline days, one day on vehicle and five days of therapy with 2% MK-927 b.i.d., after initial single-dose trials of various concentrations. IOP was not significantly different comparing baseline and vehicle treated days. Significant (p < 0.05) reductions of IOP occurred for five days lasting at least 8 hrs after each dosing. At 3 hrs after treatment with vehicle the IOP was 31.6 ± 3.4 (SE) mm Hg. Maximum reduction of IOP occurred at 3 hrs after application of MK-927, the IOP decreasing from day 1 (19.9 ± 1.0 mm Hg) to day 5 (16.5 ± 1.6 mm Hg). MK-927 appear-s to have great clinical potential.