Abstract
HYPOTHESIS:
Glaucoma is effectively treated by prostaglandin analogs. Low corneal bioavailability (<5%) of daily-instilled prostaglandin drops complemented by frequent application results in low patient compliance (<50%). One alternative route is ocular delivery via commercial hydrogel contact lens. Commercial lenses, however, release prostaglandins rapidly in a few hours owing to their small molecular size, resulting in toxic side-effects. Here, the feasibility of sustained prostaglandin, namely bimatoprost and latanoprost delivery by vitamin-Eintegrated polymeric hydrogels is explored. Inclusion of these barriers is expected to augment transport resistance and influence delivery rates.
EXPERIMENTS:
Lens immersion in vitamin-E concentrated ethanol is done to enable formation of nano-barrier depots.
FINDINGS:
Pilot in vitro studies indicate that ACUVUE® OASYS® and ACUVUE® TruEye™ lenses loaded with ∼0.2 g of vitamin-E/g of hydrogel effectively prolong bimatoprost dynamics by 10-40-fold, delivering therapeutic dosages for >10 days. Incorporation of vitamin-E into the lenses retains visible light transmission and other properties. Further, vitamin-E integration does not influence latanoprost transport. An in vivo model involving coupled mass transport in the lens and post-lens tear film (POLTF) domains predicts >50% corneal bioavailability of bimatoprost delivered via modified lenses.