Iontophoresis is a concept that dates back to the 18th century, while the first transscleral (across the white of the eye) iontophoretic application for vitreal drug delivery was reported in 1943. The process involves applying an electrical current to an ionizable substance – one capable of carrying an electric charge – to increase its mobility across a biological membrane and, through electrorepulsion, drive a like-charged drug substance into the ocular tissue.
Based on our studies and other published research, ocular iontophoresis is capable of delivering substantially higher ocular drug concentrations than traditional topical applications, leading to greater bioavailability and more sustained therapeutic effect and reducing the frequency of dosing.
For example, based on the current standard of care for anterior uveitis, patients are required to give a minimum of 154 treatments of a topical corticosteroid delivered via drops over a 4-week period. In our Phase 3 non-inferiority trial of EGP-437 administered using the EyeGate® II Delivery System (corticosteroid delivered via iontophoresis), we achieved the same rate of response as the standard of care in only two treatments, with fewer incidences of elevated IOP.