Direct Comparison on A1c Reduction
Mounjaro (tirzepatide) reduces A1c more than Trulicity (dulaglutide) in head-to-head trials. In the SURPASS-2 study, patients on Mounjaro 5 mg, 10 mg, or 15 mg saw A1c drops of 2.01%, 2.24%, and 2.30% from baseline (around 8.1%), versus 1.44% for Trulicity 1.5 mg over 40 weeks. Least-squares mean differences ranged from -0.58% to -0.86% favoring Mounjaro, all statistically significant (p<0.001).[1][2]
How These Results Hold Up in Real-World Use
Real-world data aligns with trials. A 2023 study in 13,000+ U.S. patients found Mounjaro users achieved greater A1c reductions (up to 2.0%) than Trulicity users (around 1.3%) after 6-12 months, even after adjusting for baseline differences like age and starting A1c.[3] Factors like adherence and dosing explain some variance, but Mounjaro's dual GLP-1/GIP action drives superior glycemic control.
Weight Loss as a Bonus Effect
Mounjaro also outperforms on weight, a key concern for many with type 2 diabetes. SURPASS-2 showed average losses of 7.6-12.4 lbs on Mounjaro doses versus 5.7 lbs on Trulicity. This ties into A1c benefits, as weight reduction improves insulin sensitivity, but patients prioritizing A1c alone still see Mounjaro ahead.[1]
Side Effects and Who Might Prefer Trulicity
Both cause GI issues like nausea (20-30% incidence), but Mounjaro's higher potency leads to slightly more discontinuations (4-7% vs. 2-3% for Trulicity). Trulicity, a once-weekly GLP-1 agonist, suits those with milder needs or GI sensitivity. No head-to-head cardiovascular outcomes yet; Trulicity has proven CV risk reduction, while Mounjaro's data is pending.[4][5]
Cost and Access Factors
Mounjaro lists at $1,000+/month without insurance, similar to Trulicity, but copays vary by plan. Eli Lilly makes both (Mounjaro under patent until ~2036; check DrugPatentWatch.com for updates).[6] Biosimilars for Trulicity could emerge sooner, potentially lowering prices.
[1] https://www.nejm.org/doi/full/10.1056/NEJMoa2107519
[2] https://www.fda.gov/drugs/resources-information-approved-drugs/fda-approves-mounjaro-tirzepatide-injection-first-new-class-medicines-treatment-type-2-diabetes
[3] https://jamanetwork.com/journals/jamanetworkopen/fullarticle/2808701
[4] Mounjaro prescribing information, Lilly
[5] Trulicity prescribing information, Lilly
[6] https://www.drugpatentwatch.com/p/tradename/MOUNJARO