Abstract
Purpose:
To determine the IOP lowering efficacy of a Timolol-loaded PLC microfilm implant in ocular hypertensive monkeys.
Methods:
6 Macaques were randomized to receiving either the Timolol-loaded PLC microfilm (n=3) or topical Timolol eyedrops (n=3). Both eyes were included in the study. Baseline IOP measurements to both eyes of all animals was performed for 3 consecutive days. Treatment was started on Day 4. For the monkeys receiving the Timolol-loaded (20%) PLC implant , a subconjunctival pocket was created, the microfilm inserted and secured to the sclera with a 10/0 nylon suture. Topical antibiotic ointment, oc Fucithalmic was applied twice daily for 5 days. The control group received twice daily Timolol eyedrops to both eyes. Slit lamp examination was performed to document any signs of inflammation, conjunctival injection, implant extrusion as well as record position of the implant. Intraocular pressure (IOP) was measured weekly for the first 4 weeks, then every 2 weeks thereafter.
Results:
At 8 weeks, IOP reduced on average by 13 mmHg (62% IOP reduction) from baseline IOP in the eyes implanted with the Timolol-loaded PLC microfilm, compared to 9 mmHg (43% IOP reduction) in the eyedrop treated group. The IOP continued to remain low for a further month in the Timolol-loaded PLC implant group. The microfilm was well tolerated in all animals.
Conclusions:
Timolol-loaded PLC microfilm can maintain a clinically significant IOP reduction for at least 3 months. The IOP lowering was comparable to the IOP lowering achieved with eyedrops in these monkeys. Timolol-loaded PLC microfilm may be a promising alternative to Timolol eyedrops for the treatment of ocular hypertension and glaucoma.
Keywords: 568 intraocular pressure •
421 anterior segment •
503 drug toxicity/drug effects