PROCTER & GAMBLE ZITHROMAX COPROMOTION IS OFF

PROCTER & GAMBLE ZITHROMAX COPROMOTION IS OFF after P&G and Pfizer could not finalize a joint agreement that included P&G's copromotion of the antibiotic azithromycin. Pfizer and Procter & Gamble announced April 13 that they were "unable to agree on final commercial terms" for an agreement to develop jointly P&G's osteoporosis drug risedronate following the announcement of an "interim" agreement last September ("The Pink Sheet" Sept. 21, 1992, p. 13). Under the interim deal, P&G's approximately 400 pharmaceutical sales reps began last autumn to detail the Pfizer azalide antibiotic Zithromax along with Pfizer's 700-person detail force. Zithromax sales have continued to lag behind those of Abbott's azalide antibiotic Biaxin ("The Pink Sheet" March 8, p. 7). Risedronate, a follow-on compound to P&G's etidronate (Didronel), is at the end of Phase II clinical trials for prevention and treatment of osteoporosis. Under last September's agreement, Pfizer was to have codeveloped and copromoted the drug in the U.S. and European markets. Etidronate is marketed in the U.S. for Paget's disease and heteroptic ossification. P&G is working with FDA to seek approval for etidronate for an osteoporosis indication, which did not receive an approval recommendation from FDA's Endocrinologic & Metabolic Drugs Advisory Committee at its March 1991 meeting ("The Pink Sheet" March 11, 1991, p. 3). P&G submitted additional clinical data last year for etidronate, which would be marketed as Didrocal for osteoporosis. The advisory committee wanted efficacy data beyond two years after third-year etidronate patients showed a 50% increase in new vertebral fractures compared to placebo. With the failure to reach a final agreement, Pfizer will retain the Minipress family of antihypertensives, including Minipress XL, which is approved but not marketed in the U.S., and the diuretic combination product Minizide. Both Minipress and Minizide have lost their U.S. marketing exclusivity. Under the interim agreement, P&G was to have gained rights to the Minipress family. Pfizer said it is in discussions with FDA on a manufacturing site approval for Minipress XL.