Multiple-dose, dose-response relationship for the topical carbonic anhydrase inhibitor MK-927.

The multiple-dose, dose-response curve of MK-927 was studied in a five-center, double-masked, randomized, placebo-controlled, parallel study of 2%, 1%, and 0.5% MK-927 in 76 patients with bilateral primary open angle glaucoma or ocular hypertension and intraocular pressure greater than 24 mm Hg following washout of ocular hypotensive medications. Patients received doses at 8 AM and 8 PM for 14 days, and parallel 12-hour intraocular pressure curves were performed prestudy and on day 14, with 4-hour curves on days 1 and 4. There was a significant dose-response relationship, with 0.5% MK-927 twice daily being a minimal-effect dose. Both 1% and 2% MK-927 were active through 12 hours postdose, and peak mean percent decrease in pressure at 2 hours postdose was 18.6% and 20.6%, respectively.