Addressing the significant unmet need in cataract drug delivery

Professor Eric Donnenfeld   Professor Eric Donnenfeld, New York University, USA, delivered a presentation on the changing pharmaceutical treatment patterns in cataract surgery during a Main Symposium at the XXXV Congress of the ESCRS in Lisbon. “Efficient drug delivery remains a significant unmet need, with topical drops facing not only problems with compliance, but also with low rates of absorption into the eye,” said Prof Donnenfeld. He suggested that topical medications as we know them today will change greatly over the next several years, and he proceeded to outline the possibilities on the horizon. “The mucoadhesive DuraSite vehicle delivers sustained pharmacokinetics, maintaining therapeutic concentrations in the human conjunctiva up to six days after the last dose,” he said. Nanotechnologic mucus penetrating particles (MMPs) go a step further, diffusing through the mucus membranes and increasing penetration not only into the anterior segment, but also achieving high vitreous concentrations. MMPs are currently looking for FDA approval. Moving away from eye drops, Prof Donnenfeld described other modalities, such as punctal plug drug delivery. “Ocular Therapeutix has developed a bioabsorbable, intracanalicular hydrogel plug that can deliver dexamethasone for one month,” he said. “Evolute goes a step further, incorporating a punctal occlusion device to prevent loss of drug into the canaliculus.” Intracameral delivery has definitively proven its value in endophthalmitis prophylaxis. “The next step involves bioabsorbable, intracameral depots of, for example, dexamethasone, which would guarantee postoperative compliance, allow precise dosage, avoid topical toxicity and avoid systemic absorption,” concluded Prof Donnenfeld.