Zilebesiran, a Small Interfering RNA Therapeutic Targeting Angiotensinogen: Mechanism, Clinical Evidence, Safety, and Implementation Considerations

Abstract

Hypertension remains a major global health burden, and control rates remain suboptimal because of poor medication adherence and limitations of existing therapies, including escape within the renin–angiotensin–aldosterone system. Zilebesiran, a first-in-class, subcutaneously administered small interfering RNA therapeutic, represents a promising advance in hypertension management. Through N-acetylgalactosamine-mediated hepatic delivery, zilebesiran selectively silences angiotensinogen (AGT) messenger RNA, the transcript encoding the common precursor of all angiotensin peptides. This upstream intervention reduces AGT production and produces durable blood pressure lowering that can persist for up to 6 months after a single dose. This review summarizes the mechanism of action of zilebesiran, its pharmacokinetic and pharmacodynamic properties, and the available phase 1 and phase 2 clinical evidence, including the KARDIA program. We also place zilebesiran within the evolving antihypertensive landscape by comparing it with aldosterone synthase inhibitors, dual endothelin receptor antagonists, and brain aminopeptidase A inhibitors. Finally, we discuss translational challenges, including reversal strategies for emergency situations, monitoring considerations, and potential roles for personalized dosing. Early-phase and phase 2 trials show dose-dependent and durable reductions in serum AGT and blood pressure with infrequent dosing; however, long-term safety, cardiovascular outcome benefit, and generalizability in diverse high-risk populations remain to be established, and zilebesiran remains investigational while phase 3 outcome testing is underway.