Is there a future for direct renin inhibitors?

Abstract

Importance of the field: The renin-angiotensin-aldosterone system (RAAS) is a key regulator of blood pressure (BP), as well as volume and electrolytes, in both hypertensive and normotensive individuals. Inappropriate activation of the RAAS is important in hypertension-induced cardiovascular disease (CVD) and chronic kidney disease (CKD). Renin is the rate-limiting step in the RAAS cascade, which makes direct renin inhibitors (DRIs) an attractive target for RAAS suppression and treatment of hypertension. Current regimens using either angiotensin-converting enzyme inhibitor (ACEi) or angiotensin receptor blocker (ARB) result in feedback upregulation of renin and aldosterone breakthrough, which contribute to incomplete suppression of the RAAS. Thereby, aliskiren – alone or in combination – might offer a novel therapeutic intervention to improve suppression of the RAAS, with potential to translate to improved CVD and CKD outcomes.Areas covered in this review: Herein, we present the current state of knowledge of DRIs in the preclinical and clinical realm and their antihypertensive efficacy in relation to cardiovascular and renal risk. Recent clinical trials (2007 – 2009) support the efficacy of aliskiren, and studies suggest the potential for improved CVD and CKD outcomes.What the reader will gain: An understanding of the mechanism of action of DRIs and a perspective of recent clinical trials.Take home message: The DRI aliskiren is an effective antihypertensive agent that preliminary data suggests has a beneficial effect in CVD and CKD. Combination of aliskiren with an ACEi or ARB may be better tolerated than the ACEi–ARB combination. Future work is needed to further quantify aliskiren's impact on hard CVD and CKD end points.