MYLAN's MAXZIDE IS "APPROVABLE" AT FDA: LEDERLE TO MARKET BRAND COMPETITION TO SMITHKLINE's No. 3-RANKED DYAZIDE; FINAL APPROVAL ANTICIPATED "IMMINENTLY"

Mylan's full NDA application for a triamterene/hydrochlorothiazide combo, Maxzide, reached the "approvable" stage at FDA on Sept. 28. Final FDA clearance is pending resolution of labeling issues. Mylan reportedly has responded to all follow-up questions in FDA's approvable letter to the firm. The generic mfr. expects clearance "imminently." Lederle will market the drug, which is the first combination product to contain the same ingredients as SK&F's Dyazide. Maxzide contains 50 mg hydrochlorothiazide and 75 mg triamterene, an increased dosage over Dyazide's 25 mg hydrochlorothiazide and 50 mg triamterene. The Maxzide clearance will set up an interesting brand-to-brand competition in the triamterene potassium sparing/diuretic combo market. SK&F has built Dyazide, a drug first approved in the U.S. over 20 years ago, into the third largest retail drug by sales volume. In 1983, SK&F did $210 mil. In sales of Dyazide to retail pharmacies, according to Pharmaceutical Data Services. Because of the dosage differences, Maxzide is not technically a generic equivalent for Dyazide. Lederle will be entering the potassium-sparing market with the same active ingredients as Dyazide. However, the product will have to be sold as a brand competitor. Trade sources expect Maxzide to carry a once-a-day indication. Dyazide is currently indicated for "one or two capsules twice daily after meals." Labeling notes though that "some patients may be maintained on one capsule daily or every other day." More than 70% of Dyazide use is reportedly in the once-daily dosing. Lederle has been gearing up for the Maxzide launch. In an interim statement on third quarter results issued Oct. 16, Lederle's parent, American Cyanamid, attributed a decline in medical operating earnings to "substantial pre-launch expenditures for new products." Lederle specifically cited Maxzide and "the anticipated approval by the U.S. FDA." The company further predicted a strain on near-term earnings due to "aggressive spending" for new medical products. SK&F has been working on a new formulation for Dyazide which will improve bioavailability of the drug. The company plans to submit data to FDA to support a supplemental NDA for the new formulation. The company says the clinical studies to support the new formulation have been completed and the submission is awaiting final analysis of data. The supplemental filing is "some months" away.