Semaglutide's True Value: Only 11 Patients Need Treatment for 4 Years to Prevent One Major Health Event

Secondary analysis of the SELECT trial, a randomized, double-blind, placebo-controlled phase III cardiovascular outcomes trial. 17,604 patients with overweight/obesity and established cardiovascular disease (without diabetes) received once-weekly subcutaneous semaglutide or placebo for a mean of 39.8 months. NNTs were calculated for three progressively broader composites: 3-point MACE (CV death, non-fatal MI, non-fatal stroke), an extended composite adding hospitalizations, revascularization, and non-CV death, and a cardiorenal-metabolic composite adding HbA1c ≥6.5% and a nephropathy composite.

Number needed to treat (NNT) is how payers, insurers, and health systems decide whether a drug is worth its cost. Semaglutide's headline NNT of 58 for MACE alone might not impress decision-makers, but when its broader benefits — fewer hospitalizations, less kidney disease, prevention of new diabetes — are included, the NNT drops to just 11. This analysis makes a powerful economic and clinical case that semaglutide delivers far more value than its primary trial endpoint suggests, which could influence insurance coverage and prescribing decisions for millions of patients.

The SELECT trial was already landmark evidence that semaglutide reduces cardiovascular risk in people with obesity. This NNT analysis reframes those results in terms that health economists and insurance companies use to make coverage decisions. An NNT of 11 is exceptionally favorable — comparable to or better than statins for some populations. As payers and governments debate whether to cover expensive GLP-1 drugs for cardiovascular protection (not just diabetes or weight loss), this analysis provides ammunition for broader coverage. It also sets a precedent for evaluating other GLP-1 drugs using composite endpoints that capture their multi-system benefits.

This is a secondary analysis, not the primary SELECT trial itself. The broadest composite (NNTCKM) includes outcomes of varying clinical severity, so a prevented case of new-onset diabetes is counted equally with a prevented heart attack. The SELECT trial excluded patients with diabetes, so these NNTs apply only to the overweight/obese cardiovascular disease population without diabetes. Combining multiple endpoints improves NNT by definition, so the improvement partly reflects methodology rather than additional drug efficacy.