Review of three studies to determine the efficacy and tolerance of cicletanine in the short- and long-term treatment of essential hypertension.

A double-blind multicentre study was performed initially to assess the effect of 4 weeks' treatment of cicletanine in daily doses of 12.5, 25, 50 and 100 mg, for the treatment of 60 patients with mild to moderate essential hypertension. A significant reduction in blood pressure was achieved with each dosage. Analysis of the responder rate indicated a significant dose-response relationship which was clinically relevant only for the 50 and 100 mg doses. The minimum therapeutic dosage of cicletanine for the treatment of essential hypertension was concluded to be 50 mg daily. A further 12-week study was performed in 40 patients with mild to moderate essential hypertension, commencing with a daily dose of cicletanine (50 mg) and increasing the dosage if necessary to 100 mg and 200 mg daily after 4 and 8 weeks, respectively. Blood pressure control was achieved in all patients and in the majority (70%) with a daily dosage of 100 mg cicletanine. Treatment was continued in all patients until a total duration of 2 years had been completed. Cicletanine was shown to be very well tolerated and a significant reduction in blood pressure was achieved at 6, 9, 12, 18 and 24 months. During the second year of treatment, all the patients were stabilized with a daily dosage of 50 mg cicletanine. These results are consistent with a previously reported study in 25 patients with mild to moderate essential hypertension. Twelve weeks of treatment with cicletanine (50 mg daily) produced a significantly greater reduction in blood pressure than a combination of 5 mg amiloride hydrochloride and 50 mg hydrochlorothiazide daily. This reduction was more significant for the diastolic than the systolic blood pressure measurements. A diastolic blood pressure of 90 mmHg, or less, was achieved in all patients receiving treatment with cicletanine (50 mg daily), except for two patients where the dosage was increased to 100 mg daily.