CIBA-GEIGY WARNS OF RITALIN UPCOMING SHORTAGES

CIBA-GEIGY WARNS OF RITALIN UPCOMING SHORTAGES, citing a "delay in the Drug Enforcement Administration's consideration of whether to increase the 1993 quota" for production of the Schedule II drug methylphenidate. Ciba said Oct. 5 that it "has mailed over 400,000 letters to physicians, pharmacies and pharmacy directors at medical care facilities advising them of the impending shortage." Ciba received notice of its expanded production quota Oct. 7 and has resumed "round-the-clock production" of methylphenidate. The company expects additional supplies of Ritalin to reach pharmacy shelves in "early December." Ritalin is indicated for treatment of attention-deficit hyperactivity disorder and for treatment of narcolepsy. "Historically, all supplies of methylphenidate have diminished toward the end of the year as the production quotas are exhausted by the various manufacturers," Ciba said. "This year, the situation has become more acute due to a delay in the DEA's consideration of whether to increase the 1993 quota." DEA set a 1993 quota for methylphenidate production of 3,411 kilograms. In July, the agency proposed to increase the quota for the year to 4,604 kg. Ciba-Geigy said it had essentially exhausted its original 1993 quota and could not resume full-scale production until it was given a final expanded quota by DEA. In an Oct. 7 Federal Register notice, DEA upped the 1993 allocation to 5,000 kg. Ciba's Oct. 1 letter to doctors advises physicians that "if your patients experience difficulties in obtaining Ritalin from their usual pharmacy, you may want to advise them to check with other pharmacies for supply. If the product remains unavailable, you might want to consider alternate therapies." The only other manufacturer of methylphenidate in the U.S. is Medeva's MD Pharmaceutical subsidiary. MD said it did not use up its DEA quota and continues to produce methylphenidate for its distributors. The company attributed the shortages experienced by Ciba-Geigy to expansion of the market among children for the attention-deficit disorder/hyperactivity indication. MD had briefly suspended production of methylphenidate this summer after receiving an FDA warning letter citing good manufacturing practices deficiencies ("The Pink Sheet" July 19, T&G-9). The company said it is continuing to work with FDA to resolve issues raised in the letter. A potential third manufacturer of methylphenidate, Halsey's Houba subsidiary, has been blocked from receiving a DEA quota to produce drug for bioequivalence studies pending the outcome of an administrative hearing sought by MD ("The Pink Sheet" Sept. 20, T&G-8).