(151) Modelling Total Healthcare Cost Offsets and Treatment Costs Associated with Treating Adults with Obesity with Tirzepatide and Semaglutide in US Clinical Practice Settings

Background: : Obesity poses a substantial economic burden on individuals and society, making clinically effective and cost-effective therapies essential.

Objective: : To model total healthcare cost offsets and drug treatment costs associated with weight reduction from 6 months of tirzepatide (TZP) or semaglutide (SEMA) treatment based on a comparative effectiveness research (CER) study in patients with obesity.

Methods: : The underlying clinical inputs for this economic model were obtained from the CER study of TZP vs. SEMA that included adults with a body mass index (BMI) of ≥30 kg/m2 or ≥27 and < 30 kg/m2 with ≥1 obesity-related complication and without Type 2 diabetes (T2D) initiating TZP or SEMA between Dec 2023 and June 2024. Patients were followed for 6 months and were required to adhere to initial treatment (proportion of days covered ≥80%). Mean absolute BMI and weight changes and proportions of patients achieving ≥5%, ≥10%, ≥15%, and ≥20% weight loss at 6 months were estimated using multivariable regression models weighted with propensity scores.
Total annual healthcare costs at treatment initiation and at 6 months of treatment were projected for TZP and SEMA groups based on a previous study that estimated the causal relationship between BMI and annual total healthcare costs. Cost offsets were calculated by subtracting projected annual total healthcare costs at 6 months from that at treatment initiation. Treatment costs per responder and costs per pound lost were calculated as dividing drug treatment costs over 6 months (using Wholesale Acquisition Cost) by % of patients achieving weight reduction response categories and by mean absolute weight reduction for TZP and SEMA groups, respectively.

Results: : The CER study included 1,003 TZP and 1,393 SEMA patients, with a mean (SD) age of 48.4 (12.2) and 49.1 (11.9) years, 69.9% and 73.2% female, mean (SD) BMI of 38.3 (7.2) and 38.4 (7.1) kg/m2, respectively. Annual total healthcare cost offsets post-treatment were projected to be $683 higher in TZP-treated patients ($3,037) than in SEMA-treated patients ($2,354). TZP was projected to incur lower treatment costs per pound lost than SEMA ($260 vs. $422) and lower treatment costs per responder than SEMA: ≥5% ($8,154 vs. $11,502); ≥10% ($11,889 vs. $23,463); ≥15% ($23,005 vs. $65,662); and ≥20% ($62,705 vs. $231,546).

Conclusions: : Among adults with obesity without T2D, real-world TZP treatment for 6 months was projected to result in lower annual total healthcare costs and lower treatment costs per weight reduction responder and per pound of weight lost than SEMA.

Sponsorship:: Eli Lilly and Company