MEBENDAZOLE GENERIC PRODUCTS SHOULD HAVE CLINICAL STUDIES

MEBENDAZOLE GENERIC PRODUCTS SHOULD HAVE CLINICAL STUDIES to ensure equivalence to the innovator product, Vermox, Janssen Research Foundation maintained in an Oct. 21 citizens petition to FDA. "Any company producing a product containing mebendazole cannot rely on a bioequivalence study alone to prove efficacy," Janssen said. "Full clinical studies should be conducted against all the helminths for which the approved drug is indicated (hookworm, roundworm, whipworm and pinworm) to support an efficacy and safety claim." Full clinical studies or studies with clinical endpoints are needed because mebendazole has "strong local activity in the gastrointestinal tract," and therefore "the bioavailability of the drug is very low and the major route of elimination is an unchanged drug in the feces," the Johnson & Johnson subsidiary explained. Vermox is marketed worldwide by Janssen and is available in the U.S. in 100 mg tablets. Third world countries comprise the biggest market for the product, Janssen noted. The anthelmintic may be susceptible to U.S. generic competition after an April 18, 1989 patent expires. Janssen also asked that companies be required to "conduct bioequivalence and excretion (urine and feces) studies to assure that the product has safety equivalent to the innovator drug (i.e., that plasma levels are, at the most, minimal and that excretion is mainly in the feces)." In addition, Janssen said, tests should be done to "ensure that the drug substance is the correct polymorph," the one on which Janssen's NDA was based. Companies should also see to it that the "correct polymorph does not revert to the less efficacious form over the life of the drug substance and drug product."