Aliskiren--mode of action and preclinical data

Hypertension is one of the major health care problems worldwide since it markedly increases the risk for development of heart disease, stroke, generalized vascular disease, and renal failure. The renin-angiotensin system (RAS) with its major end-product angiotensin II (Ang II) plays a fundamental role in blood pressure regulation through direct and indirect mechanisms. Pharmacologically, we can inhibit the RAS using angiotensin-converting enzyme inhibitors and AT1 receptor blocker. Inhibiting renin directly with a clinically useful drug eluded pharmacologists until recently. However, the once-daily, orally effective, small-molecule, direct renin inhibitor aliskiren has recently changed this state of affairs. Aliskiren, with its 40-h half-life and ideal pharmacokinetics, can now address angiotensin production directly at its rate-limiting step. A novel transgenic rat model outfitted with the human renin and angiotensinogen genes allowed the testing of aliskiren in an animal model. Preclinical data demonstrated that aliskiren prolonged survival, decreased cardiac hypertrophy and the inducibility of arrhythmias, proteinuria, and attenuated inflammation. All these features might result in improved target-organ damage. Studies in humans attest to an effective blood pressure-lowering action, a largely side effect-free profile, and the option of several combination therapies. Aliskiren is the first of a novel antihypertensive drug class. The preclinical data is very promising. Nevertheless, for the evaluation of its potency in humans, we have to wait for more clinical data.