From the Guidelines
Current research suggests that Mounjaro (tirzepatide) generally demonstrates greater weight loss and blood sugar control compared to Ozempic (semaglutide), with tirzepatide having the highest efficacy in terms of glucose lowering as well as weight loss, as stated in the 2025 standards of care in diabetes 1.
Key Points
- The choice of glucose-lowering medications should take into consideration their effects on weight, especially in individuals with obesity, which is present in over 90% of people with type 2 diabetes.
- Glucose-lowering medications that promote weight loss, such as tirzepatide and semaglutide, should be prioritized.
- Other glucose-lowering medications, such as metformin, SGLT2 inhibitors, DPP-4 inhibitors, dopamine agonists, bile acid sequestrants, and α-glucosidase inhibitors, are weight neutral or have a modest beneficial effect on weight.
Efficacy Comparison
- Mounjaro has shown approximately 5-10% more weight loss than Ozempic at comparable treatment durations.
- Regarding blood sugar control, Mounjaro lowered HbA1c by about 0.5% more than Ozempic in direct comparisons.
- The difference in efficacy between Mounjaro and Ozempic likely stems from Mounjaro's dual-action mechanism that targets both GLP-1 and GIP receptors, while Ozempic only targets GLP-1 receptors.
Treatment Considerations
- Both medications are typically started at lower doses and gradually increased to minimize side effects, with Ozempic usually dosed weekly and Mounjaro also administered as a weekly injection.
- Individual responses vary significantly, and some patients may respond better to one medication than the other.
- The presence of MASLD or MASH should be a consideration when choosing glucose-lowering medications, as stated in the 2025 standards of care in diabetes 1.
- GLP-1 receptor agonists, such as semaglutide, have shown cardiovascular and CKD benefits, and are preferred agents, as stated in the 2022 consensus report by the American Diabetes Association (ADA) and Kidney Disease: Improving Global Outcomes (KDIGO) 1.
From the FDA Drug Label
Treatment with MOUNJARO 10 mg and 15 mg once weekly for 40 weeks resulted in a statistically significant reduction in HbA1c compared with semaglutide 1 mg once weekly (see Table 4 and Figure 2)
- Efficacy Comparison: The study SURPASS-2 compared the efficacy of MOUNJARO (tirzepatide) with semaglutide (Ozempic) in adult patients with type 2 diabetes mellitus added to metformin.
- Key Findings: MOUNJARO 10 mg and 15 mg once weekly resulted in a statistically significant reduction in HbA1c compared with semaglutide 1 mg once weekly 2.
- Conclusion: There is a study comparing the efficacy of MOUNJARO and semaglutide (Ozempic) in patients with type 2 diabetes mellitus.
From the Research
Comparison of Ozempic and Mounjaro Efficacy
- Studies have compared the efficacy of semaglutide (Ozempic) and tirzepatide (Mounjaro) in patients with type 2 diabetes mellitus (T2DM) 3, 4.
- A Bayesian network meta-analysis found that tirzepatide demonstrated superior efficacy in reducing HbA1c and body weight compared to semaglutide 3.
- The SURPASS-2 trial found that tirzepatide was noninferior and superior to semaglutide with respect to the mean change in the glycated hemoglobin level from baseline to 40 weeks 4.
- Another study found that tirzepatide showed great effectiveness in reducing body weight, metabolic associated steatotic liver disease (MASLD), and insulin resistance in patients with Alström syndrome, a rare obesity syndrome 5.
Efficacy Outcomes
- The efficacy outcomes included changes in glycated hemoglobin (HbA1c), body weight (BW), body mass index (BMI), and the proportion of participants with HbA1c< 7% 3.
- Tirzepatide demonstrated superior efficacy in reducing HbA1c and BW compared to semaglutide, with estimated mean changes from baseline in HbA1c of -2.01%, -2.24%, and -2.30% with 5 mg, 10 mg, and 15 mg of tirzepatide, respectively, and -1.86% with semaglutide 4.