Contact Lenses as Ophthalmic Drug Delivery Systems: A Review

Abstract

Ophthalmic drugs used for the treatment of various ocular diseases are commonly administered by eye drops. However, due to anatomical and physiological factors, there is a low bioavailability of the active principle. In order to increase the drug residence time on the cornea to adequate levels, therapeutic contact lenses have recently been proposed. The polymeric support that constitutes the contact lens is loaded with the drug; in this way, there is a direct and effective pharmacological action on the target organ, promoting a prolonged release of the active principle. The incorporation of ophthalmic drugs into contact lenses can be performed by different techniques; nowadays, the soaking method is mainly employed. To improve the therapeutic performance of drug-loaded contact lenses, innovative methods have recently been proposed, including the impregnation with supercritical carbon dioxide. This updated review of therapeutic contact lenses production and application provides useful information on the most effective preparation methodologies, recent achievements and future perspectives.

Lab‐on‐a‐Contact Lens: Recent Advances and Future Opportunities in Diagnostics and Therapeutics

“…[22,23] Currently, ocular drug delivery methods to treat eye diseases mainly rely on eye drops and ointments for non-invasive drug administration. [24,25] However, limitations such as poor patient compliance, low bioavailability, and high systemic drug uptake, still make current treatment strategies not optimally efficient enough for managing ocular disease. [26] To solve these shortcomings, the SCL-based drug delivery wearable platform has been devised and developed.…”

“…[ 27–29 ] SCL‐based drug delivery systems are designed to achieve efficient drug encapsulation, accurate drug dose delivery, sustained drug release, adequate drug bioavailability, and better patient compliance. [ 25,29 ] As a very recent example, the first clinical trial investigating LLT‐BMT1, a drug‐eluting SCL product from MediPrint Ophthalmics, has been shown to be safe and well‐tolerable for the treatment of glaucoma. These uplifting trial results will undoubtedly boost the advances in CL products for patients suffering from conceivably‐disabling ocular diseases such as glaucoma and diabetic retinopathy.…”

PVA-Based Hydrogels Loaded with Diclofenac for Cartilage Replacement

“…Drug release depends on the material’s composition and porosity, which control, respectively, the chemical and steric interactions between the drug molecules and the polymer network [ 11 ]. Although several strategies can be applied to load the drug into the hydrogels and control its release (incorporation of drug-loaded nanoparticles or other colloidal nanostructured systems, molecular imprinting, addition of ligands/functional monomers to the polymeric matrix, or incorporation of molecules that work as diffusion barriers [ 34 ]), soaking them into the drug solution is the most straightforward and less expensive loading method, but usually results in an initial burst and a limited release period [ 35 ]. However, depending on the drug and polymeric matrix, suitable drug release profiles may be achieved.…”

Soft Contact Lenses as Drug Delivery Systems: A Review

“…The dynamic of this research is evidenced by the number of publications that appear in scientific journals. Table 1 summarises the review papers that have been published in recent years [ 1 , 2 , 3 , 4 , 5 , 6 , 7 , 8 , 9 , 10 , 11 , 12 , 13 , 14 , 15 , 16 , 17 , 18 , 19 , 20 , 21 , 22 , 23 , 24 , 25 , 26 , 27 , 28 , 29 , 30 , 31 ].…”