The Composite Number Needed to Treat for Semaglutide in Populations with Overweight or Obesity and Established Cardiovascular Disease Without Diabetes.

Introduction: Number needed to treat (NNT), an outcome measure derived from the estimated risk results of clinical trials, is widely used to demonstrate value to stakeholders by identifying how many patients require treatment to avoid one event of interest. However, NNTs calculated for primary trial endpoints may underestimate a treatment's value by not considering other outcomes. In this secondary analysis of data from the SELECT cardiovascular (CV) outcomes trial, we aimed to determine the NNT for semaglutide for major adverse cardiovascular events (MACE), in addition to NNTs when other clinically and payer-relevant outcomes are included.

Methods: This study is a secondary analysis of data from the randomized, double-blind SELECT trial (ClinicalTrials.gov NCT03574597) of once-weekly subcutaneous administration of semaglutide compared with placebo in 17,604 patients with overweight or obesity and with established cardiovascular disease (CVD) (39.8 months mean follow-up). The outcomes were NNT (based upon the trial's composite primary endpoint of death from cardiovascular causes, non-fatal myocardial infarction, non-fatal stroke), NNT (inclusive of NNT, hospitalization for any cause, coronary revascularization, and non-CV death), and NNT (inclusive of NNT, glycated hemoglobin level [HbA] ≥ 6.5%, and a 5-point nephropathy composite).

Results: The relative risk reductions observed for the events comprising the NNTs were 20% (NNT), 20% (NNT), and 41% (NNT). At 1 and 4 years post initiation of semaglutide, NNT was 125 and 58, NNT was 49 and 25, and NNT was 20 and 11, respectively.

Conclusion: When clinically and payer-relevant outcomes from the SELECT trial are included in calculations of NNT, semaglutide was associated with greater risk reductions and lower estimates of NNT than for the primary endpoint alone. Our findings suggest that including the broader effects of semaglutide beyond the primary trial endpoint recognizes additional value to stakeholders.