Effect of different dose schedules of 0.15% unoprostone isopropyl on intraocular pressure and pupil size in the glaucomatous beagle

The changes in intraocular pressure (IOP) and pupil size (PS) after instillations of 0.15% unoprostone isopropyl (Rescula, Novartis Ophthalmics, Duluth, GA) were investigated in the spontaneous glaucoma Beagle model. From the first-day baseline IOP of 27.3 +/- 3.2 mmHg placebo eye and 32.8 +/- 5.1 mmHg control eye, the mean +/- standard error of the mean (SEM) diurnal changes after 0.15% unoprostone, at 8 AM once-daily for the next 4 days, were 15.5 +/- 1.3 mmHg, 14.7 +/- 1.9 mmHg, 16.1 +/- 1.1 mmHg, and 17.0 +/- 1.5 mmHg, respectively, and were significantly different from the control eye. After 0.15% unoprostone was instilled at 8 Pm, the mean +/- SEM baseline changes from the baseline IOP (insert drug eye 9 AM) in the drug eyes were 5.9 +/- 2.5 mmHg, 5.2 +/- 4.1 mmHg, 9.7 +/- 2.5 mmHg, and 3.6 +/- 3.6 mmHg, respectively. When 0.15% unoprostone was instilled twice-daily, the mean +/- SEM baseline IOP (insert drug eye 9 AM) changes were 13.6 +/- 0.7 mmHg, 13.9 +/- 1.4 mmHg, 11.3 +/- 1.0 mmHg, and 9.3 +/- 1.4 mmHg, respectively, and were significantly different from the control eyes. Miosis occurred within 2 hours and lasted several hours. Unoprostone isopropyl instilled once-daily (AM or Pm), as well as twice-daily, produces significant decreases in IOP and PS in the glaucomatous Beagle.