First renin inhibitor, aliskiren, for the treatment of hypertension

Aim of the review To systematically analyze the efficacy and safety of aliskiren for the treatment of hypertension in comparison to placebo, other monotherapy, and various combination therapies. Method A PubMed database (1966-June 2008) search was conducted with aliskiren as a search term with limits of humans, written in English, and in title only. Phase III pivotal clinical studies retrieved by PubMed database and resources such as printed labeling, approval letter, pharmacology reviews, and medical reviews posted in Drug@FDA website were evaluated with regard to study design and outcomes of efficacy and safety. Results Six Phase III pivotal clinical studies compared various doses of aliskiren to placebo and some studies compared aliskiren to treatment with other monotherapies or combinations. Aliskiren in doses of 300 mg showed a statistically significant reduction in both systolic and diastolic blood pressure versus placebo. Comparison to other antihypertensive treatments suggest that aliskiren doses of 150 and 300 mg may induce blood pressure changes similar to those seen with moderate doses of hydrochlorothiazide or angiotensin receptor blockers. Aliskiren in combination with angiotensin receptor blockers or hydrochlorothiazide showed additional blood pressure reduction only when higher doses of aliskiren were used. Aliskiren appears to be well tolerated, with diarrhea being the only statistically significant adverse event. Conclusion Aliskiren is a novel antihypertensive that exerts its effects through the direct inhibition of renin. Although the drug is well tolerated, its modest effects on blood pressure and the present lack of evidence of impact on objective cardiovascular outcomes appear to limit its utility in the general treatment of hypertension at this time.