SQUIBB's CAPOTEN COULD GET ONCE-DAILY ANTIHYPERTENSIVE CLAIM; ADVISORY COMMITTEE SUGGESTS INCLUDING ONCE-DAILY INFORMATION IN CLINICAL PHARMACOLOGY SECTION
Executive Summary
Squibb's Capoten labeling should be able to mention in the Clinical Pharmacology section once-a-day efficacy for hypertension when used with a diuretic, FDA's Cardio-Renal Drugs Advisory Committee unanimously agreed (with one abstention) at its May 5 meeting. The recommendation also presumably applies to Capozide (captopril/hydrochlorothiazide). Both Capoten and Capozide labeling currently recommend b.i.d. or t.i.d. administration for hypertension. A labeling change in the Clinical Pharmacology section noting 24-hour duration could be followed later by a change in the Dosage and Administration section. FDA noted at the meeting that Squibb had requested that the once-daily information be added to the Clinical Pharmacology section pending the submission of more complete data to support a full-fledged; once-daily antihypertensive claim. The study that was identified by the committee as most persuasive found that the change from baseline (minus placebo) in seated diastolic blood pressure at the end of the 24-hour dosing interval and after eight weeks of therapy was 6.22 mm Hg for patients receiving captopril 50 mg and hydrochlorothiazide 25 mg; 4.22 mm Hg for patients receiving captropril 25 mg and hydrochlorothiazide 12.5 mg; 1.72 mm Hg for patients receiving hydrochlorothiazide 12.5 mg; and 1.27 mm Hg for patients receiving captopril 25 mg. The committee also considered changing the recommended t.i.d. Capoten dosage regimen for congestive heart failure to a b.i.d. schedule, but voted four to two that a submitted studies did not sufficiently support such a change. Several committee members, however, commented that they "intuitively" believe a b.i.d. regimen is effective and pointed out that a b.i.d. v. t.i.d. study found essentially similar effects of the two regimens on exercise endurance and other efficacy parameters. The committee additionally evaluated two studies on the effect of captopril on ventricular function in post-myocardial infarction patients. One of the studies found an improvement in hemodynamic function compared to placebo, while the other showed no statistical difference compared to placebo, but did find a benefit over the baseline period. The committee agreed that the studies did not provide any conclusive information about captopril's effect in the post-MI population, but said the data looked promising. The committee noted that more conclusive results should be obtained from the ongoing SAVE study, which is evaluating survival effects of Capoten in roughly 2,000 post-MI patients. Results from that study are not expected before 1991.