Cost of Semaglutide, Tirzepatide Prohibitive Despite Significant Benefits
A new economic evaluation estimates that semaglutide would need to drop its current price by 81.9% and tirzepatide by 30.5% to be cost effective.
Semaglutide and tirzepatide could each avert tens of thousands cases of cardiometabolic disease each year among individuals with obesity. However, their high costs renders them economically unviable under current pricing, according to a new analysis published in JAMA Health Forum.
Despite demonstrating superior improvements in life expectancy compared with alternative obesity medications, both GLP-1 receptor agonists exceed the study’s accepted cost-effectiveness threshold, raising concerns over accessibility and health equity.
In fact, researchers led by Jennifer H. Hwang, DO, MSc, pathways clinical instructor in the section of general internal medicine, department of medicine at the University of Chicago, found that both incretin mimetics would require significant price reductions to meet those standards. Tirzepatide’s price would need to drop by 30.5%, while semaglutide would require an 81.9% reduction to achieve an incremental cost-effectiveness ratio (ICER) of $100,000 per quality-adjusted life year (QALY).
Hwang and colleagues utilized the Diabetes, Obesity, Cardiovascular Disease Microsimulation model to evaluate the cost-effectiveness of 4 FDA-approved antiobesity medications: semaglutide (Wegovy, Novo Nordisk), tirzepatide (Zepbound, Eli Lilly), naltrexone/bupropion (Contrave, Currax Pharmaceuticals), and phentermine/topiramate (Qsymia, Vivus). The analysis incorporated patient data from the 2017-2020 National Health and Nutrition Examination Survey for of 4823 individuals (representing 126 million eligible US adults) aged 20 to 79 years who would meet the clinical trial inclusion criteria for these drugs: body mass index (BMI) of 30 kg/m2 or BMI between 27 and 29.9 kg/m2 and at least 1 weight-related comorbidity (ie, diabetes, hypertension, dyslipidemia, or cardiovascular disease). Mean age of the cohort was 48 years and half were women; mean baseline BMI was 34.7, and 85% had at least one weight-related comorbidity.
Quality-Adjusted Life Years
When investigators compared each of the 4 medications with lifestyle modification alone on outcomes, all increased life expectancy and QALYs gained. Tirzepatide led with the most life-years gained per 100 000 eligible population, at 48,649, followed by semaglutide (35,634 QALYs), phentermine-topiramate (20,153 QALYs), and naltrexone-bupropion (11,406 QALYs), according to the study.
The 2 GLP-1 receptor agonists also were associated with larger gains in QALY (incremental gains of 0.35 and 0.25 over lifestyle modification alone), greater savings in health care costs over time, and reduced loss of productivity as a result of improved health, but the much higher costs compared with the 2 other medications offset the important benefits, the authors noted.
Specifically, semaglutide had the highest ICER at $467,676 per QALY, followed by tirzepatide, at $197,023 per QALY—both exceeding the conventional $100,000 per QALY threshold for cost-effectiveness. In contrast, phentermine/topiramate had an ICER of $85,229 per QALY and naltrexone/bupropion was deemed cost-saving compared with lifestyle intervention alone. A drug was considered to be cost-effective if it had an ICER of $100,000 or less compared with lifestyle intervention alone. Total costs were adjusted for 2023 US dollars.
Simulation Assumptions
In the simulation, eligible adults were treated with one of the 4 medications plus lifestyle intervention or received the lifestyle intervention alone. The simulations accounted for projected long-term cardiometabolic outcomes, assumed weight loss in the first 2 years as well as first year discontinuation related to adverse events. SSR Health data were used to estimate net prices for semaglutide and tirzepatide while prices for naltrexone/bupropion and phentermine/topiramate were obtained from federal supply schedule prices. Annual health care costs were estimated using Medical Expenditure Panel Survey data. Hwang et al computed QALYs using the US health-related quality of life prediction model that is based on variables including age, sex, race/ethnicity and specific health conditions.
“Policy solutions are crucial to improve antiobesity medication affordability and access. Since the US Food and Drug Administration approved the first GLP-1 RA nearly 2 decades ago, only 1 generic GLP-1 RA has been approved,” the authors emphasized, “primarily due to extensive patent and regulatory strategies that significantly delay generic entry.”
The research team also pointed to potential cost-effective weight maintenance approaches, such as long-term lifestyle modification programs, “food is medicine interventions,” and lower-dose maintenance GLP-1 mimetics after initial use of drugs from the class that could help individuals sustain meaningful clinical benefits. “Although these alternatives potentially yield fewer health gains than antiobesity medications alone, they may result in substantial long-term savings in health care expenditures.”
And, finally, they concluded, “Efforts to reduce the net prices of new antiobesity medications are essential to ensure equitable access to highly effective” pharmacotherapeutic options.
Hwang JH, Laiteerapong N, Huang ES, Kim DD. Lifetime health effects and cost-effectiveness of tirzepatide and semaglutide in US adults. JAMA Health Forum. 2025;6(3):e245586. doi:10.1001/jamahealthforum.2024.5586
