prostaglandin-f2-isopropyl-ester and Ocular-Hypertension

A study was carried out to assess the clinical efficacy of PhXA41, a new phenyl-substituted prostaglandin F2 alpha-isopropyl ester analogue, using a single administration in 35 subjects with ocular hypertension or primary open-angle glaucoma. PhXA41 caused a dose-dependent intraocular pressure (IOP) reduction which continued 24 hours or more after administration. The mean IOP reduction 8 hours after treatment compared with the baseline IOP was 3.4, 4.9 and 5.9 mmHg for the doses of 25, 50 and 100 micrograms/ml, respectively. Although slight conjunctival hyperemia occurred in some patients, it disappeared by the next day with no treatment. No aqueous flare or cells were detected, no significant change in pupillary diameter was found, and no systemic symptom was reported. Thus, PhXA41 was well tolerated in subjects with ocular hypertension or primary open-angle glaucoma. Furthermore, its IOP-reducing effect was so long-lasting that a once daily application may suffice for clinical use.

Topics: Adult; Aged; Conjunctiva; Dinoprost; Dose-Response Relationship, Drug; Drug Tolerance; Female; Glaucoma, Open-Angle; Humans; Hyperemia; Intraocular Pressure; Latanoprost; Male; Middle Aged; Ocular Hypertension; Ophthalmic Solutions; Prostaglandins F, Synthetic

In a randomized, double-masked, placebo-controlled study, 0.25 microgram (n = 11) or 0.5 microgram (n = 13) of prostaglandin F2 alpha-1-isopropyl ester (PGF2 alpha-IE) was applied topically twice daily for 8 days to one eye of ocular hypertensive or chronic open-angle glaucoma patients. Compared with contralateral, vehicle-treated eyes, PGF2 alpha-IE significantly (P less than 0.05) reduced intraocular pressure (IOP), beginning 4 hours after the first 0.5-microgram dose and lasting at least 12 hours after the fourteenth dose, with a significant (P less than 0.005) mean reduction of 4 to 6 mmHg maintained throughout the last day of therapy with either dose. A contralateral effect was not observed. Mean tonographic outflow facility was significantly (P less than 0.05) higher in PG-treated compared with vehicle-treated eyes (0.17 +/- 0.02 versus 0.12 +/- 0.01 microliter/minute/mmHg, respectively; +/- standard error of the mean) for the 0.5 microgram dose. Conjunctival hyperemia reached a maximum at 30 to 60 minutes after PGF2 alpha-IE application. Some patients reported mild irritation lasting several minutes after some doses. Visual acuity, accommodative amplitude, pupillary diameter, aqueous humor flare, anterior chamber cellular response, Schirmer's test, pulse rate, and blood pressure were not significantly altered. Our findings show that PGF2 alpha-IE is a potent ocular hypotensive agent and a promising drug for glaucoma therapy.

Topics: Aged; Conjunctiva; Dinoprost; Dose-Response Relationship, Drug; Double-Blind Method; Female; Glaucoma, Open-Angle; Humans; Hyperemia; Intraocular Pressure; Male; Middle Aged; Ocular Hypertension; Patient Compliance; Random Allocation; Tonometry, Ocular

It has been shown that prostaglandin A2 (PGA2) is a more potent ocular hypotensive agent in cats than other PG free acids. We report here that significant IOP reduction can be achieved in normotensive cat eyes with the use of even lower doses of PGA2-1-isopropyl ester (PGA2-IE) than with PGA2, PGF2 alpha-1-isopropyl ester (PGF2 alpha-IE), or any other known ocular hypotensive agent. Furthermore, single applications of 0.5 microgram of PGA2-IE maintain significant IOP reductions for at least 24 hr. This hypotensive effect is enhanced during the first 3-5 days of daily treatment. Significant IOP reductions were maintained for several months as long as PGA2-IE was applied daily or at least once every 48 hr. None of the cats manifested signs of discomfort in response to treatment with doses ranging from 0.10 to 1.25 micrograms of PGA2-IE. Moreover, the extent of anterior chamber flare was less than that typically observed after the topical application of hypotensive doses of PGE2, PGD2, PGF2 alpha, or the esters or tromethamine salt of PGF2 alpha. Although it is possible that the human eye would respond differently to PGs of the A type, the results of these studies suggests that PGA2-IE or other esters of derived PGs of the A type, and probably the B type, may offer significant therapeutic advantages over the PGF2 alpha tromethamine salt and PGF2 alpha-IE, which have been shown to exert significant hypotensive effects on normal and glaucomatous human eyes.

Topics: Administration, Topical; Animals; Cats; Dinoprost; Dose-Response Relationship, Drug; Female; Intraocular Pressure; Male; Ocular Hypertension; Prostaglandins A; Prostaglandins A, Synthetic; Prostaglandins F, Synthetic; Time Factors