A new generation of weight-loss medicines is delivering results that exceed those of some of today's best-known treatments, according to a new study led by researchers at McGill University and the Lady Davis Institute for Medical Research.

Researchers reviewed 38 randomized clinical trials involving more than 25,000 adults with obesity or excess weight but not diabetes to evaluate the effectiveness and safety of GLP-1-based weight-loss drugs.

Among approved therapies, tirzepatide, the active ingredient in Mounjaro, helped patients lose up to 19 per cent of their body weight. Semaglutide – used in Wegovy and Ozempic – achieved results approaching 15 per cent in several studies.

Newer drugs still being tested produced even greater reductions. Retatrutide was associated with weight loss of up to 22 per cent, while amycretin reached nearly 24 per cent in clinical trials.

The lead author is available to discuss the findings:

Areesha Moiz, medical student, McGill University; Clinical Research Assistant, Lady Davis Institute for Medical Research, Jewish General Hospital.

areesha.moiz [at] mail.mcgill.ca (English)