AZD3427

AZD3427 is a novel, long-acting fusion protein that acts as a selective agonist of the relaxin family peptide receptor 1 (RXFP1). It is engineered as an analog of human relaxin-2, fused to the Fc fragment of human IgG1 to extend its half-life. Relaxin is a vasodilatory hormone with antifibrotic effects and plays a role in cardiovascular homeostasis. AZD3427 mimics these beneficial effects by activating RXFP1, leading to vasodilation and potential reduction in fibrosis. The drug has demonstrated improved pharmacokinetics compared to native relaxin-2, allowing for less frequent dosing (weekly or biweekly subcutaneous injections). Preclinical studies showed significant improvements in cardiac function—including increased ejection fraction, cardiac output, and stroke volume—without adverse events. Clinical trials are ongoing for heart failure (including both reduced and preserved ejection fraction) and pulmonary hypertension due to left heart disease[1][4][6][7].