Comparing Analytical Methods for Composite End Points in Clinical Trials: Insights from the Vericiguat Global Study in Subjects with Heart Failure With Reduced Ejection Fraction Trial

Abstract

In VICTORIA (Vericiguat Global Study in Subjects with Heart Failure with Reduced Ejection Fraction), participants with heart failure (HF) and reduced ejection fraction, vericiguat decreased the primary composite outcome (time to first HF hospitalization [HFH] or cardiovascular death [CVD]) (897 events) compared with placebo (972 events) (hazard ratio, 0.90; 95% confidence interval [CI], 0.82-0.98; P = .02). In this prespecified secondary analysis, we applied the weighted composite end point (WCE) and the win ratio (WR) methods to provide complementary assessments of treatment effect. The WCE method estimated the mean HFH-adjusted survival based on prespecified weights from a Delphi panel of the VICTORIA executive committee and national leaders: mild (weight per event, 0.39), moderate (0.5), or severe (0.67) HFH, and CVD (1.0). The unmatched WR was estimated for the descending hierarchy of CVD, then recurrent HFH. The WCE used all 3412 primary clinical events: 875 severe HFH (vericiguat, 416/ placebo, 459), 1614 moderate HFH (767/847), 68 mild HFH (38/30), and 855 CVD (414/441). Improved HFH-adjusted survival occurred with vericiguat (mean 78.2% vs 75.6%, difference 2.4%, 95% CI, 1.7%-3.2%, P < .0001). Based on a comparison of 6,375,624 pairs, the WR of 1.13 (95% CI 1.03-1.24, P = .01) also indicated improved clinical outcomes with vericiguat. The results of the WCE and WR methods were consistent with the primary analysis of the time to first HFH or CVD. Although both WCE and WR assessed recurrent events, the WCE allowed inclusion of all recurrent events, insights on the severity of HFH events, and an absolute measure of the participant-treatment experience. This approach complements conventional assessment, better informing consumers of new therapeutics and future trial designs.