Clinical positioning of indapamide sustained release 1.5mg in management protocols for hypertension

Indapamide sustained release (SR) 1.5mg is a new galenic formulation that is characterised by a relatively constant plasma concentration at steady state, with only minor fluctuations during the 24-hour period. A dose-titration study of 3 doses of indapamide SR (1.5, 2 and 2.5mg) given once daily has shown that the 3 dosages are equipotent in lowering blood pressure, and have an effect similar to that of indapamide immediate-release (IR) 2.5mg; all were statistically more effective than placebo. The percentage of hypertensive patients whose serum potassium was less than 3.4 mmol/L was significantly lower after indapamide SR 1.5mg than after indapamide IR 2.5mg. Neither indapamide formulation had any significant effects on lipid profile, glucose, urea and serum creatinine; only uric acid was slightly raised during the 2-month study. In an equivalence study, indapamide SR 1.5mg and IR 2.5mg produced similar blood pressure reductions (within the equivalence limit of +/-5mm Hg), whereas the percentage of patients whose serum potassium fell to less than 3.4 mmol/L was lower in the IR 1.5mg group than in the SR 2.5mg group. Antihypertensive treatment with indapamide SR 1.5mg once daily produced reductions in blood pressure in elderly patients with systolic/diastolic or isolated systolic hypertension that were similar to reductions with amlodipine 5 mg/day. The incidence of adverse effects was very low in all studies with indapamide SR 1.5mg and very similar to that in the placebo group, confirming thereby the improvement in the efficacy: tolerance ratio with the new indapamide compound.