Aliskiren-based therapy reduced geometric mean plasma renin activity by 63% at 26 weeks, compared to a 143% increase with ramipril (p<0.05), and reductions persisted 4 weeks after withdrawal.
RCT (n=842)
double-blind
randomised
Does aliskiren-based therapy compared to ramipril-based therapy improve blood pressure and plasma renin activity in patients with hypertension?
Aliskiren-based therapy provides greater blood pressure reduction and sustained suppression of plasma renin activity compared to ramipril in hypertensive patients.
Absolute Event Rate: -63% vs 143%
p-value: p=<0.05
INTRODUCTION: This subgroup analysis assessed the effects of treatment based on the direct renin inhibitor, aliskiren, or the angiotensin-converting enzyme inhibitor, ramipril, on plasma renin activity (PRA), plasma renin concentration (PRC) and other biomarkers in a 26-week randomised, double-blind trial. Changes in PRA and PRC after stopping treatment were also assessed. METHODS: After placebo run-in, 842 patients (mean sitting diastolic blood pressure (BP) 95-109 mmHg) were randomised to aliskiren 150 mg or ramipril 5 mg. Dose titration and hydrochlorothiazide addition were allowed after Week 6 and 12, respectively, for inadequate BP control. Patients completing active treatment were re-randomised to current regimen or placebo during a 4-week posttreatment phase. RESULTS: BP reductions were independent of baseline PRA at Week 12, were greater with aliskiren- than ramipril-based therapy at Week 26 (17.9/13.3 vs. 15.2/12.0 mmHg, p<0.05) and persisted for longer after stopping aliskiren. Aliskiren-based therapy reduced geometric mean PRA (-63%, p<0.05; n=103), while ramipril-based therapy increased PRA (+143%, p<0.05; n=100) at Week 26; PRC increased in both groups (aliskiren: +224% n=33, ramipril: +145% n=39, both p<0.05). Four weeks after stopping aliskiren-based therapy, PRA remained 52% below pre-treatment baseline; PRA returned to baseline 2 weeks after stopping ramipril-based therapy. CONCLUSIONS: Aliskiren-based therapy produced sustained BP and PRA reductions over 26 weeks; ramipril-based therapy lowered BP and increased PRA. PRA reductions persisted 4 weeks after stopping aliskiren, suggesting an inhibitory effect beyond the elimination half-life of the drug.
Andersen et al. (Fri,) conducted a rct in hypertension (n=842). aliskiren vs. ramipril 5 mg was evaluated on geometric mean plasma renin activity (PRA) change at Week 26 (p=<0.05). Aliskiren-based therapy reduced geometric mean plasma renin activity by 63% at 26 weeks, compared to a 143% increase with ramipril (p<0.05), and reductions persisted 4 weeks after withdrawal.