MERCK’s PROSCAR (FINASTERIDE) APPROVED JUNE 19 AFTER 14-MONTH REVIEW

Executive Summary

Merck's benign prostatic hyperplasia treatment Proscar (finasteride) was approved by FDA June 19 after a 14-month agency review. Merck submitted an NDA for Proscar 5 mg on April 15, 1991. In February, Proscar cleared FDA's Endocrinologic and Metabolic Drugs Advisory Committee by a six-to-one vote that the drug's benefits outweighed its risks for the treatment of benign prostatic hyperplasia ("The Pink Sheet," Feb. 10, p. 9). However, the committee also recommended that Merck conduct a five-year extension of its Phase III trial and conduct a number of Phase IV followups to look at long-term safety and efficacy of the drug and to collect data on the impact of finasteride therapy in different patient populations. Specific questions included: the optimum patient population for the drug; the effect of the drug on lipid levels, bone density, glucose levels and other conditions of the elderly; the drug's profile in non-white and elderly populations; and the incidence of conditions such as sexual function alterations, urinary retention and urinary tract infections. The committee also was concerned that the ability to detect prostate cancer might be negatively affected by treatment with Proscar. At the time of the advisory committee meeting, Merck outlined a number of Phase IV studies either underway or in the planning stage ("The Pink Sheet" Feb. 10, p. 11). The approval letter for Proscar notes March 24 and June 19 correspondence from Merck detailing the company's planned followup and Phase IV trials. The proposed studies listed in the approval letter closely follow the recommendations of the advisory committee. FDA is currently reviewing a patient package insert for Proscar expected to be completed "in the near future," according to the approval letter. The company submitted the PPI for review on June 18. FDA told Merck that it can begin marketing without the PPI but that it "should be distributed with Proscar" once the agency's review and the company's validation are completed. Although Merck has not yet released pricing information on Proscar, company Chairman Roy Vagelos, MD, told securities analysts in New York last fall that Proscar would be priced "fairly at a price that most people can afford" ("The Pink Sheet," Nov. 11, 1991, T&G-2). Vagelos was among the first industry leaders to call for responsible pricing of pharmaceuticals, and he has committed Merck to restrained price growth. As a chronic age-related condition, benign prostate enlargement has been estimated to affect 60% of men over 50. Proscar is the first product to be approved for that use. Abbott has an NDA pending at FDA covering use of its currently marketed alpha blocker Hytrin (terazosin) for the treatment of BPH. Pfizer also is studying its alpha blocker Cardura (doxazosin) for the same indication.