New Oral Drug AZD5462 Shows Promise in Early Heart Failure Trial

LUMINARA Trial Design and Patient Cohorts

According to the European Society of Cardiology, the double-blind, dose-ranging LUMINARA trial enrolled 375 total patients with chronic heart failure who were already receiving stable, maximally tolerated therapies. The study split participants into two distinct cohorts based on their left ventricular ejection fraction. The first cohort included 235 patients with heart failure and a reduced ejection fraction of 35% or lower. The second cohort comprised 140 patients with heart failure and a preserved ejection fraction between 41% and 55%. Researchers randomised patients in a 1:1:1:1 ratio to receive either a placebo or once-daily doses of AZD5462 at 20 mg, 80 mg, or 360 mg over a 24-week period.

Cardiac Function and Vasodilation Results

Data presented by Professor James Januzzi from the Baim Institute for Clinical Research, Massachusetts General Hospital, and Harvard Medical School indicated distinct responses between the two patient groups. Among patients with reduced ejection fraction, the lowest 20 mg dose of AZD5462 produced the most beneficial effects on cardiac function. At 24 weeks, this dose decreased the end systolic volume index—a measure of adverse cardiac remodelling—by 5.4 mL/m2 from baseline compared to placebo, with a p-value of 0.054. Secondary endpoints, including changes in ejection fraction, also showed the greatest improvements at the 20 mg dose. In the preserved ejection fraction cohort, AZD5462 reduced the systemic vascular resistance index by 19% for the 20 mg dose, 21% for the 80 mg dose, and 15% for the 360 mg dose at 24 weeks, with all values achieving statistical significance at p ≤ 0.021.

Safety Profile and Future Research Directions

The trial reported a low incidence of adverse events with no excess risk linked to AZD5462 treatment. Investigators observed a mild lowering of blood pressure, but the frequency of significant hypotension remained comparable between the drug and placebo groups. Furthermore, the study noted no evidence of significant volume overload, a complication that affected higher doses of earlier relaxin-like drugs. Professor Januzzi stated that target engagement was successfully demonstrated in both cohorts. Following these phase IIb findings, researchers indicate that larger randomised trials focused on clinical outcomes are now warranted for AZD5462.