OBJECTIVES: Obesity is one of the most prevalent chronic conditions in the US. While lifestyle changes remain the primary approach, there's a growing use of GLP-1 receptor agonists to treat obesity. This study aimed to assess the cost-effectiveness of semaglutide plus lifestyle counseling versus liraglutide plus lifestyle counseling in non-diabetic adults with obesity.

METHODS: A Markov model was constructed from the payer’s perspective to model the average quality-adjusted life years (QALYs) and the costs of both treatments, with future costs and QALYs discounted by 3.0% annually. People enter the model at age 49.13 with an initial BMI of 37.1, of whom 50% were female. People move between three states, lose weight, treatment discontinuation, and death, on a monthly cycle. Data were mainly derived from STEP 8 clinical trial. Costs were obtained from Red Book 2023. The model examined a period of 5 years to capture the long-term influence of GLP-1 medication on weight loss. The main outcome was incremental cost-effectiveness ratios (ICERs). A strategy was considered cost-effective if the ICER was less than the willingness-to-pay threshold ($100,000 per QALY gained).

RESULTS: At 5 years, semaglutide plus lifestyle counselling was the preferred strategy, with an ICER of $1.2 million per QALY gained vs liraglutide plus lifestyle counselling. However, $1.2 million per QALY gained is greater than the willingness-to-pay threshold. Model results were most sensitive to the cost of medications and the rate of severe adverse events for both arms.

CONCLUSIONS: The result indicates that, after 5 years, semaglutide plus lifestyle counseling will be cost-effective compared to liraglutide plus lifestyle counseling for non-diabetic adults with obesity. However, the ICER value was over the willingness-to-pay threshold. This study did not consider other health benefits related to weight loss, so the QALY gained from both interventions might be underestimated.