Preliminary experiences with HOE 498, a novel long-acting converting enzyme inhibitor, in hypertensive patients.

The effect of various doses of the new angiotensin-converting enzyme inhibitor HOE 498 was compared with that of placebo in patients with mild essential hypertension. When a single dose of 2.5 mg of the drug was given, blood pressure was not significantly reduced despite a fall in converting enzyme levels. Single doses of 5 or 10 mg did reduce blood pressure, but complete inhibition of converting enzyme was apparent only with the 10-mg dose. Acute administration of a 20-mg dose proved to be unsuitable, since this was associated with too large a fall in pressure and the occurrence of symptomatic orthostatic hypotension. Although converting enzyme and blood pressure tended to recover in part 12 h after administration of the drug, both variables remained low even after 48 h.