Efficacy and safety of a fixed low-dose perindopril/indapamide combination in essential hypertension. A randomised controlled study

This multicenter, double-blind, parallel-group study was designed to assess the efficacy and the safety of fixed low dose combination perindopril 2 mg/indapamide 0.625 mg (Per/Ind) versus atenolol 50 mg (Ate). After a 4-week placebo run-in, 446 hypertensive patients (mean age : 55.8 +/- 11.0 years) were randomised to receive Per/Ind or Ate for 12 weeks. The primary outcome measures were the changes in trough supine systolic and diastolic blood pressure (sSBP, sDBP) between baseline and the last observation. Equivalence was assessed in an intention-to-treat analysis using a two one-sided tests procedure. Per/Ind and Ate decreased sSBP by -20.5 mmHg and -20.1 mmHg, respectively; the 90% confidence interval [-2.3; 1.5] of the intertreatment difference (-0.4 mmHg) fell within the predefined equivalence interval [-8; +8 mmHg]. Similarly, the sDBP decreased by -15.1 mmHg (Per/Ind) and -16.2 mmHg (Ate) with an intertreatment difference of 1.1 mmHg whose 90% confidence interval [-0.1; 2.2 mmHg] fell within the predefined equivalence interval [-4; +4 mmHg]; thus antihypertensive efficacy of Per/Ind and Ate were equivalent (P <0.001). In patients older than 65, Per/Ind induces a statistically greater decrease in sSBP than Ate (P <0.05). Per/Ind was well tolerated. Further controlled studies are needed to confirm these results on a long-term period.