SQUIBB CAPOTEN IS FIRST LINE ANTIHYPERTENSIVE IN NORMAL RENAL FUNCTION PATIENTS; CLINICALS FIND NEUTROPENIA FREQUENCY IN RENALLY UNIMPAIRED LESS THAN ONE IN 8,600
Executive Summary
Squibb's Capoten (captcaptopril) is first line therapy for hypertension in patients with normal renal function, according to the drug's newly revised labeling. FDA approved new labeling for the drug, including an indication covering all degrees of hypertension, on July 1. Captopril "may be used as initial therapy for patients with normal renal function, in whom the risk [of neutropenia/agranulocytosis] is relatively low," the package insert states (for text of the new indication, see box below). FDA expanded the indication for captopril after a nearly three-year supplemental NDA review. The agency based its decision on clinical studies which found that the risk of neutropenia in the normal renal group was "one patient out of over 8,600 exposed." The drug's labeling initially limited use to last line treatment because the extent of the neutropenia/agranulocytosis risk was unknown. The principal population at risk, the studies found, was the group of renally impaired patients with collagen vascular diseases. According to the new Warnings section, in the clinical trials, neutropenia occurred in 3.7% of those patients. In patients with "some degree" of renal failure, but no collagen vascular disease, "the risk of neutropenia in clinical trials was about one per 500, a frequency of over 15 times that for uncomplicated hypertension," the insert says. For those populations, captopril treatment is reserved for individuals who develop "unacceptable side effects" to other drugs or "fail to respond satisfactorily to drug combinations." The insert notes that, "in general, neutrophils returned to normal in about two weeks after captopril was discontinued, and serious infections were limited to clinically complex patients. About 13% of the cases of neutropenia have ended fatally, but almost all fatalities were in patients with serious illness, having collagen vascular disease, renal failure, heart failure or immunosuppressant therapy, or a combination of these complicating factors." In a July 3 press release announcing the apoval, Squibb said: "This significant broadening of the indicated usage for Capoten means that the drug may be prescribed as first-step therapy for the great majority of hypertensive patients." Based on Capoten's accelerating sales, use for less severe antihypertensive indications has already begun to be reflected in current medical practice. Pharmaceutical Data Services recently reported that Capoten sales in 1985 could exceed $110 mil. CAPOTEN's REVISED HYPERTENSION INDICATION [Reprinted from FDA's revised package insert, approved July 1] CAPOTEN (captopril) is indicated for the treatment of hypertension. In using CAPOTEN, consideration should be given to the risk of neutropenia/agranulocytosis (see WARNINGS). CAPTOEN may be used as initial therapy for patients with normal renal function, in whom the risk is relatively low. In patients with imparied renal function, particularly those with collagen vascular disease, captopril should be reserved for hypertensives who have either developed unacceptable side effects on other drugs, or have failed to respond satisfactorily to drug combinations. CAPOTEN is effective alone and in combination with other antihypertensive agents, especially thiazide-type diuretics. The blood pressure lowering effects of captropril and thiazides are approximately additive.