VASOTEC (ENALAPRIL) IS "APPROVABLE," FDA TELLS MERCK; DRUG IS SECOND ACE INHIBITOR

Merck's new heart drug Vasotec (enalapril) is "approvable," FDA told the company on Nov. 1. Under agency procedures, the classification indicates that review of Merck's NDA for the new angiotensin converting enzyme (ACE) inhibitor is complete and approval will be forthcoming once final labeling is prepared by the company and approved by FDA. Once approved, Vasotec will be the second ACE inhibitor after Squibb's Capoten to receive U.S. market approval. Merck is also awaiting approval for its antibiotic/enzyme inhibitor Primaxin (imipenem/cilastatin), which the company expects to receive by the end of the year. Capoten was originally approved for use only in the most severe forms of hypertension, and did not win FDA approval for use in all stages of hypertension until this past year. Vasotec would get a big boost if its initial approved labeling carries the same broad uses as the modified labeling of Capoten. Merck is seeking approval of Vasotec for use in treatment of congestive heart failure and in all degrees of hypertension. In June 1984, Vasotec was recommended for approval by FDA's Cardio-Renal Drugs Advisory Cmte. for both indications. Vasotec would also get a boost if it were to be approved without carrying Capoten's label warnings for neutropenia and proteinuria, and bold print warnings for patients with impaired renal function or autoimmune disease, or for patients taking drugs affecting white blood cell count. The FDA advisory cmte. suggested at its June 1984 meeting that the Merck drug not be burdened with "class" side effect warnings. Enalapril has recently been approved under the brand name Renitec in the U.K., W. Germany and France.