I want to break down something critically important from the SELECT trial that I think gets lost in the media noise about "weight-loss drugs."
The SELECT trial enrolled 17,604 adults with established cardiovascular disease and BMI ≥27 but without diabetes. Semaglutide 2.4 mg weekly vs. placebo. Primary endpoint: time to first MACE (CV death, nonfatal MI, nonfatal stroke).[1]
"Semaglutide reduced the risk of MACE by 20% (HR 0.80; 95% CI, 0.72–0.90; P<0.001) over a mean follow-up of 39.8 months."
Here is the key finding that everyone needs to internalize: the cardiovascular benefit was observed early — within the first few months — before clinically significant weight loss had occurred. The Kaplan-Meier curves separated by approximately month 4-6. Median weight loss at that point was only ~5-6%.
Furthermore, mediation analyses showed that weight loss accounted for only a fraction of the MACE reduction. The anti-inflammatory and direct vascular effects appear to be driving much of the benefit.
This has massive implications for how we conceptualize GLP-1 receptor agonists. They are not merely "weight loss drugs with cardiac side-benefits." They are cardiovascular drugs that also happen to cause weight loss.
[1] Lincoff AM, Brown-Frandsen K, Colhoun HM, et al. Semaglutide and Cardiovascular Outcomes in Obesity without Diabetes. N Engl J Med. 2023;389(24):2221-2232. doi:10.1056/NEJMoa2307563