OBJECTIVES: Real-world evidence on adherence to glucagon-like peptide-1 receptor agonist (GLP-1RA) in elderly or disabled patients is limited. Patient adherence to an antidiabetic regimen is a clinical challenge when considering the medical complexities of T2DM in elderly patients and other comorbidities associated with aging. GLP-1RA therapies such as exenatide once weekly (QW) and liraglutide once daily (QD) are an increasingly used class of drugs with proven efficacy and tolerability. The current study examined adherence to medication in patients age ≥ 65 years with T2DM initiating a GLP-1RA. METHODS: The study used medical and pharmacy claims between 2010 and 2013 for Medicare members in a US health plan diagnosed with T2DM and were new initiators of either exenatide QW (n=537) or liraglutide QD (n=3673) during that time frame and were continuously enrolled for 6 months pre- and post-index. Proportion of Days Covered (PDC) ≥ 80% was used to determine post-index adherence. Logistic regression models controlled for baseline demographics, comorbidities and T2DM treatments. RESULTS: A significantly higher percentage of patients on exenatide QW had a PDC ≥ 80% (43.2%) vs liraglutide QD (35.0%, χ2, p<.01).  Adjusted results indicated patients on liraglutide QD were 20.1% (p<.01) less likely to be adherent than patients on exenatide QW. Two other significant factors associated with lower adherence were:  evidence for cardiovascular disease and plan type. The mean proportion of days covered showed patients on exenatide QW had a slightly higher medication possession rate of GLP1-RA compared with patients on liraglutide QD: 63.5% vs. 61.5% (ns). CONCLUSIONS: Results from this retrospective study suggest that overall adherence to GLP-1RAs was low, but was better with exenatide QW. Patients 65 years and older treated with exenatide QW had a significantly higher adherence rate compared to liraglutide QD.  Further research is needed to validate these findings in other patient populations.