FDA BIOEQUIVALENCE DIV, WORKING ON GUIDELINE PROTOCOL FOR HALOPERIDOL STUDIES

FDA is developing a protocol on bioequivalence studies for generic versions of McNeil's Haldol (haloperidol), the agency's Bioequivalence Div. Director Shirikant Dighe, PhD, told a seminar in Washington, D.C. on June 13. The seminar was sponsored by the Legal Times and Law and Business. Noting that Haldol's patent will expire in 1986, Dighe explained that "we have a protocol written by one of our scientists. She was worked on this area a long time at NIH and she wrote a protocol on [haloperidol] after consulting the current literature." McNeil also prepared a protocol on haloperidol and recently submitted it to FDA in the form of a citizen petition ("The Pink Sheet" June 10, T&G-3). The FDAer referred to the McNeil petition and told the group that it will be reviewed "in due time." The Bioequivalence Div. chief reported that his office is nearing completion of the first 15 protocol guidelines for top selling drugs identified by FDA as priorities. Nine of the 15 have already been issued, Dighe said, and "I hope to have in the next 30 days another six or seven come out." The agency is trying to "cover the drugs that are most important," he noted, "antiarrhythmic drugs, antidiabetic drugs, [and] some of the newer antibiotic drugs." In addition to preparing protocols in-house, Dighe and Office of Drug Standards Deputy Director James Morrison, PhD, stressed that FDA will comment on protocols submitted by individual firms. "Companies can propose a protocol if they feel that by supplying that information to the agency a better study or an adequate bioequivalence study will be available for evaluation and review . . . that will assure the bioequivalence of the generic product to the listed or brandname product," Dighe said. Morrison advised the group: "If you are thinking of marketing a drug through an ANDA, one of the first things you should do is check with Dr. Dighe's division as to what kind of guidance they have . . . whether it's formal guidance or informal type advice that they may be able to give you in a meeting or a phone conversation or letter." One of the several protocol proposals submitted by firms thus far is headed for approval. "I think, we will adopt [it] in toto," Dighe commented. Another "we will have to reject because of the difficulties I see with the protocol." In addition to McNeil, at least one other firm has submitted a protocol for generic equivalence testing, Roche for Valium (diazepam).