Daily disposable contact lenses as a platform for ocular drug delivery of cyclosporine A

Ophthalmic drug delivery is an important area of research that aims to improve the efficacy and convenience of treatment for various eye conditions. There are multiple ways in which drugs can be delivered to the eye, including eye drops, ointments, gels, and inserts. The most prevalent way of administering medication to the eye is through eye drops. They are easy to use and can be self-administered by patients. Nonetheless, eye drops have the disadvantage of being prone to removal by tears, which may result in insufficient drug absorption and reduced effectiveness. Irregular use of active substances can exacerbate the disease, resulting in prolonged treatment with questionable efficacy. Soft contact lenses that serve as ophthalmic drug delivery systems (DDS) can become a viable substitute for traditional treatments. These polymeric lenses can be embedded with various active compounds, some of which are not readily soluble in water or physiological fluids. One such drug is Cyclosporine A (CyA), an immunosuppressant with a high molecular weight and hydrophobic properties, chronically used to treat dry eye syndrome (DES). The article discusses the development of a method for modifying Hilafilcon B contact lenses obtained from drugstores with Cyclosporine A (CyA). The drug was administered to the lenses using an immersion technique, and the process parameters were monitored to control drug release efficiency and profile. The drug release was measured in an Artificial Lacrimal Fluid (ALF) buffer, mimicking tear fluid with a pH of 7.9. The stability of CyA in this buffer was assessed. For the parameters used, the best drug application and release profile was achieved by immersing the contact lenses for 24 hours at 25 °C in a CyA solution containing 20 μg/ml of the active substance and adding 5 mg/ml of Vitamin E.