(097) Real-World Patterns in GLP-1 RA Switching from 2018-2023 in the US

Background: Glucagon-like peptide-1 receptor agonists (GLP-1 RAs) have surged in popularity, however increasing demand and global shortages may prevent patients from accessing their prescribed medications.

Objectives: To describe demographic and temporal patterns in GLP-1 RA switching.

Methods: Using a subset of EHR data from Truveta, we identified patients with a GLP-1 RA dispense between 2018 and October 2023. EHR data from Truveta included BMI values, conditions, encounters, and medication dispensing for a collective of US healthcare systems. Switching was defined as being dispensed a different drug than the previous month. We describe the drugs and months with the highest rates of switching. Results are presented overall and for populations with overweight/obesity (BMI>=27) and type 2 diabetes (T2D).

Results: Of 1,051,391 eligible patients, 10.9% experienced at least one drug switch. While the overall population is primarily between 45-64 years of age (overall: 51.9%; switched: 57.4%), female (62.1%; 64.3%), white (69.6%; 72.0%), and not Hispanic or Latino (79.1%; 81.2%), the population who switched had higher percentages in each of these groups. Compared to the overall population, slightly higher rates of switching occurred for people with overweight/obesity (overall: 59.8%; switching: 60.4%), T2D (41.9%; 44.2%) and those who initiated treatment on or before 2021 (41.2%; 57.1%). The population who switched had higher initiation rates on liraglutide labeled for T2D (switched: 20.7%; overall: 11.8%) and lower initiation rates on semaglutide labeled for T2D (switched: 25.1%; overall: 35.5%).

Switching rates were highest in January 2023 (3.0%, 3.0%, and 3.1% of the overall, T2D and overweight/obesity populations, respectively). The majority of the overall population switched from dulaglutide labeled for T2D (26.1%) or semaglutide labeled for T2D (21.0%). The population primarily switched to semaglutide labeled for T2D (24.5%) or tirzepatide labeled for T2D (14.9%). Similar trends were seen for both sub-populations.

The overweight/obesity population also experienced high rates of switching in June 2023 (2.6%). Patients primarily switched from dulaglutide labeled for T2D (17.5%). Patients primarily switched to semaglutide labeled for T2D (28.0%).

Conclusions: With the increase in GLP-1 RA use we found switching patterns varied by medication, with higher rates observed for medications approved earlier, which have longer follow-up time on average. Within certain months there were high rates of switching from and switching to semaglutide for T2D, potentially representing geographic variation in shortages. Future research is needed to understand how switching effects treatment efficacy.