In the advent of an increasingly aging population and due to the popularity of electronic devices, ocular conditions have become more prevalent. In the world of medicine, accomplishing eye medication administration has always been a difficult task. Despite the fact that there are many commercial eye drops, most of them have important limitations, due to quick clearance mechanisms and ocular barrers. One solution with tremendous potential is the contact lens used as a medication delivery vehicle to bypass this constraint. Therapeutic contact lenses for ocular medication delivery have attracted a lot of attention because they have the potential to improve ocular bioavailability and patient compliance, both with minimal side effects. However, it is essential not to compromise essential features such as water content, optical transparency, and modulus to attain positive in vitro and in vivo outcomes with respect to a sustained drug delivery profile from impregnated contact lenses. Aside from difficulties like drug stability and burst release, the changing of lens physico-chemical features caused by therapeutic or non-therapeutic components can limit the commercialization potential of pharmaceutical-loaded lenses. Research has progressed towards bioinspired techniques and smart materials, to improve the efficacy of drug-eluting contact lenses. The bioinspired method uses polymeric materials, and a specialized molecule-recognition technique called molecular imprinting or a stimuli-responsive system to improve biocompatibility and support the drug delivery efficacy of drug-eluting contact lenses. This review encompasses strategies of material design, lens manufacturing and drug impregnation under the current auspices of ophthalmic therapies and projects an outlook onto future opportunities in the field of eye condition management by means of an active principle-eluting contact lens.
Keywords: bioavailability; composite; contact lens; drug delivery; gas-permeable; hydrogel.