See the DrugPatentWatch profile for trulicity
How Trulicity and Mounjaro Work for Weight Loss
Trulicity (dulaglutide) is a GLP-1 receptor agonist that mimics one gut hormone to boost insulin release, slow digestion, and reduce appetite. Mounjaro (tirzepatide) is a dual GLP-1 and GIP receptor agonist, targeting two hormones for stronger effects on blood sugar, fullness, and fat metabolism. This dual action gives Mounjaro an edge in weight reduction trials.[1][2]
Weight Loss Results from Clinical Trials
In head-to-head relevant data, Mounjaro outperforms Trulicity. The SURPASS-2 trial showed patients on Mounjaro (10-15 mg weekly) lost 12-15 kg (about 22-25% body weight) over 40-72 weeks, compared to 7-10 kg (around 10-15%) on Trulicity (1.5 mg weekly).[3] Real-world studies echo this: Mounjaro users average 15-20% weight loss at one year, while Trulicity averages 5-10%.[4] Trulicity has FDA approval only for type 2 diabetes (with weight loss as a secondary benefit); Mounjaro is approved for diabetes and, as Zepbound (same drug), for chronic weight management in adults with obesity or overweight plus comorbidities.
Dosing Schedules and Administration
Both are once-weekly subcutaneous injections via pre-filled pens. Trulicity starts at 0.75 mg, maxes at 4.5 mg. Mounjaro starts at 2.5 mg, titrates to 15 mg. Higher doses of Mounjaro drive better weight loss but require slower ramps to minimize side effects.[1][2]
Common Side Effects and Tolerability
Gastrointestinal issues dominate for both: nausea (20-40%), vomiting, diarrhea, and constipation. Mounjaro has higher rates at peak doses (up to 25% severe nausea) but similar dropout rates in trials (5-10%). Trulicity causes less intense GI effects overall. Both carry boxed warnings for thyroid cancer risk in rodents (human risk unclear) and pancreatitis. Long-term data is stronger for Trulicity (approved since 2014).[3][5]
Cost and Insurance Coverage
Without insurance, Trulicity costs $900-1,100 monthly; Mounjaro/Zepbound runs $1,000-1,300. Savings cards drop both under $25/month for eligible patients. Medicare covers Trulicity routinely for diabetes; Mounjaro coverage varies by plan, with Zepbound often requiring prior authorization for weight loss. Shortages have hit Mounjaro harder recently.[6]
Who Gets Better Results and When to Choose One
Mounjaro suits those prioritizing maximum weight loss (e.g., BMI >30 or stalled on single GLP-1s), especially with diabetes. Trulicity fits milder needs, simpler titration, or patients sensitive to side effects. Neither is first-line for weight alone—lifestyle changes come first. Consult a doctor for personalized fit, as heart benefits (seen in trials for both) factor in.[3][4]
Sources
[1] Trulicity Prescribing Information (FDA)
[2] Mounjaro Prescribing Information (FDA)
[3] SURPASS-2 Trial (NEJM)
[4] Real-World Weight Loss Comparison (JAMA)
[5] Zepbound Prescribing Information (FDA)
[6] GoodRx Pricing Data