Sustained Delivery of Olopatadine from Vitamin-E Loaded Contact Lenses.

Topical antihistamines, such as olopatadine hydrochloride, an H1 receptor antagonist, are commonly prescribed for treating allergic conjunctivitis. Drug delivery via eye drops has many deficiencies including a short residence time due to tear drainage via the nasolacrimal duct, which results in a low bioavailability and potential for side effects. These deficiencies could be mitigated by a drug-eluting contact lens such as the recently approved ACUVUE THERAVISION™ WITH KETOTIFEN which is a daily disposable etafilcon, a drug-eluting contact lens with ketotifen (19 μg per lens). Here, we investigate the feasibility of designing a drug-eluting lens with sustained release of olopatadine for treating allergies using an extended wear lens. Nanobarrier depots composed of vitamin-E (VE) are formed through direct entrapment by ethanol-driven swelling. The drug-loaded lenses are characterized for transparency and water content. release is measured under sink conditions and fitted to a diffusion control release model to determine diffusivity and partition coefficient. studies indicate that ACUVUE OASYS and ACUVUE TruEye™ lenses loaded with ∼0.3 g of VE/g of hydrogel effectively prolong olopatadine dynamics by 7-fold and 375-fold, respectively. Incorporation of VE into the lenses retains visible light transmission and other properties. The VE incorporation in commercial lenses significantly increases the release duration offering the possibility of antiallergy extended wear lenses.