Study weight loss drug tirzepatide leads to a 50 pound weight loss average.
Great news - a new weight loss medication called tirzepatide leads to an average of over 50 pounds of weight loss per person taking the highest dose in a study involving 2,359 participants! New data released from the Phase III SURMOUNT-1 clinical trial shows that tirzepatide leads to the most weight loss seen with any medication to date - an average of over 22% on the highest dose of 15 mg.
Tirzepatide is a combination of two agents - a glucagon-like insulinotropic polypeptide (GIP) receptor agonist and a glucagon-like peptide-1 (GLP-1) receptor agonist. GIP and GLP-1 are two incretins (or hormones) that the gut releases which signals the brain regarding satiety (or fullness).
There are several GLP-1 receptor agonists that are already approved for weight loss - liraglutide (Saxenda) which was approved for weight loss in Canada in 2015 and semaglutide (Wygovy) which was just approved for weight loss in 2021. Both of these agents were first approved for diabetes - liraglutide was approved as Victoza in 2010 and semaglutide was approved as Ozempic in 2018.
Like both liraglutide and semaglutide, tirzepatide is a weekly injection. Because it works on the incretin system, tirzepatide has similar side effects: Nausea, vomiting, diarrhea and constipation.
Also like both liraglutide and semaglutide, tirzepatide will likely be approved for diabetes first, as early as this year. The SURMOUNT-1 trial published in The Lancet in 2021 showed promising results for diabetes control.. An application has already been put into the FDA and Health Canada. Canadian approval usually lags American approval. The tentative approvals for weight loss would likely come later in both countries.
The take-home point here is that weight loss medicine is rapidly evolving. Currently, we have 4 medications (Xenical, Contrave, Saxenda, Wygovy) approved for weight loss in Canada and within the next 2 years, we are likely to have this fifth medicine (tirzepatide) available. The latest medications are as effective as some types of bariatric surgery.