TOPICAL OPHTHALMIC VASOCONSTRICTOR/ANTIHISTAMINE COMBOS

Executive Summary

TOPICAL OPHTHALMIC VASOCONSTRICTOR/ANTIHISTAMINE COMBOS should be approved for an Rx-to-OTC switch for treating "redness and itching," FDA's Ophthalmic Drugs Subcommittee recommended at a Dec. 17 meeting. A subcommittee of the agency's Anti-Infective Drugs Advisory Committee, the panel made its decision despite FDA concerns over the safety and labeling of topical vasoconstrictor/antihistamine ophthalmic combinations. To address the agency's concerns, the subcommittee modified the prescription indication, allergic conjunctivitis. Patients with more severe or varied symptoms, such as pain behind the eyes or a purulent discharge would be advised by the product's labeling to seek immediate medical attention. Iolab Pharmaceuticals' Vasocon-A currently is the only prescription vasoconstrictor/antihistamine product approved for allergic conjunctivitis. Iolab, a J&J subsidiary, has petitioned FDA to grant Vasocon-A three years of exclusivity on the basis that approval of the NDA for the formulation was based on clinical studies essential to approval. Vasocon-A was approved last spring, but FDA is believed to be leaning against exclusivity because the NDA approval constitutes a DESI update. Most antihistamine/vasoconstrictor therapies currently marketed for ophthalmic use have been classified as only "possibly effective" by the National Academy of Sciences, and FDA has announced its intention to withdraw these products from the market unless further data are forthcoming. Nonetheless, representatives from Bausch & Lomb attending the advisory subcommittee meeting reported that their company is "very interested in the concept" of an OTC combination product. FDA Anti-Infective Drugs Division reviewer Wiley Chambers, MD, described for the subcommittee FDA's concerns about the safety and labeling of such combinations if they are approved for OTC use. FDA is particularly worried that adding an antihistamine to vasoconstrictor therapies may mask symptoms of serious eye disease, preventing patients from seeking medical treatment when appropriate. "It is possible to get some complications from the misuse of OTC ophthalmic products," asserted Chambers. The FDAer also expressed doubts as to whether the symptoms of allergic conjunctivitis could be alleviated within 72 hours -- the amount of time current OTC labeling allows for treatment to take effect before directing consultation with a physician. Most subcommittee members acknowledged that Chamber's concerns were legitimate but did not feel that they warranted prohibiting an OTC switch. "The masking of signs and symptoms is something that is part of every OTC ophthalmic preparation from Boric Acid on up," argued Michael Cobo, associate professor of ophthalmology at Duke University Medical School. Although such preparations potentially "may delay" diagnosis, they do not "frequently delay this with a condition" that threatens vision.