Real-world 6-month persistence, adherence, and effectiveness of GLP-1 medications for overweight and obesity in a Medicaid population

BACKGROUND: Glucagon-like peptide-1 (GLP-1) receptor agonists, including a dual GLP-1/glucose-dependent insulinotropic polypeptide (GIP) agonist, have expanded treatment options for overweight and obesity. However, real-world data within Medicaid populations remain limited. OBJECTIVE: To assess 6-month persistence, adherence, and effectiveness of GLP-1 and GLP-1/GIP therapies among Massachusetts Medicaid (MassHealth) members. METHODS: This retrospective, claims-based analysis identified continuously enrolled MassHealth adults, with or without diabetes, initiating GLP-1 or GLP-1/GIP treatment with semaglutide (Wegovy) or tirzepatide (Zepbound) between July 1, 2024, and December 31, 2024. The co-primary outcomes were persistence, defined as no more than 56 days between fills, and adherence, defined as proportion of days covered (PDC) of at least 80%. A key secondary outcome examined the rate at which a subgroup of members achieved at least a 5% reduction in body weight from baseline as documented on prior authorization (PA) recertification at 6 months. RESULTS: Among 7,493 members, rates of persistence and adherence to treatment were 60.8% and 60.1%, respectively. Member-specific factors associated with lower rates of persistence and adherence included male sex, age (