Tirzepatide vs Mazdutide
It is the weekly shot behind Mounjaro and Zepbound, used for diabetes and weight loss. Large trials show 15% to 21% weight loss. It is a weekly weight-loss shot approved in China. Two trials in over 1,000 adults there showed about 15% weight loss, but no US trial has finished.
Both sit at grade A: strong human evidence. Tirzepatide: FDA approved. Mazdutide: In clinical trials.
Evidence
AStrong human evidence
AStrong human evidence
Human studies cited
Animal or cell studies cited
Why the grade
Tirzepatide's weight-loss use rests on the SURMOUNT program of randomized placebo-controlled trials, the largest being SURMOUNT-1 with 2,539 adults, plus trials in type 2 diabetes, sleep apnea, weight maintenance and diabetes prevention. Every approved indication was granted on randomized data, so it grades A.
Mazdutide has completed multiple phase 3 randomized placebo-controlled trials in China: GLORY-1 in 610 adults with overweight or obesity and GLORY-2 in 461 adults with obesity, plus the DREAMS trials in type 2 diabetes, and it won two approvals on that basis. That meets the A definition. The limits are that nearly all trial participants were Chinese, no cardiovascular outcomes trial has reported, and US data are limited to one phase 2 trial of 179 people.
FDA
FDA approved
Tirzepatide is approved by the FDA as Mounjaro (2022) for type 2 diabetes in adults, extended to children 10 and older and to cardiovascular risk reduction in adults with type 2 diabetes and established cardiovascular disease, and as Zepbound (2023) for chronic weight management and for moderate to severe obstructive sleep apnea in adults with obesity.
In clinical trials
Not approved by the FDA for any use. Mazdutide is approved in China, where the NMPA cleared it in June 2025 for chronic weight management in adults with overweight or obesity and in September 2025 for glycemic control in type 2 diabetes. In the US it is investigational, with Eli Lilly holding the rights, one US phase 2 trial published and no phase 3 result or FDA filing reported.
Sold for
Tirzepatide is the weight-loss injection that outperformed semaglutide, cutting body weight by about a fifth in trials.
Mazdutide is pitched as the next step after tirzepatide: a weekly dual agonist that adds glucagon receptor activity to GLP-1 for more weight loss and liver fat reduction, and it is already being sold by gray-market peptide vendors in the US.
Studies say
Multiple large randomized trials show weight loss of 15 to 21 percent, better glucose control than other diabetes drugs, and improvement in sleep apnea, with weight regain after stopping, which is a clean A.
Two phase 3 trials in more than a thousand Chinese adults produced about 15 percent weight loss versus placebo over 48 to 60 weeks and led to approval in China, which grades A, although no US trial has finished and no outcomes trial exists.
Class
Dual GIP + GLP-1 receptor agonist
GLP-1 / glucagon dual agonist
Route
Injection
Injection