OBJECTIVES: Dulaglutide once-weekly is a novel glucagon-like peptide 1 receptor agonist for the treatment of type 2 diabetes mellitus (T2DM) that is expected to be approved for reimbursement by the Taiwan National Health Insurance Administration in 2016. The objective of this study was to examine the cost-effectiveness of dulaglutide 1.5 mg and 0.75 mg as a treatment for patients with T2DM initiating injectable therapy after failing oral antidiabetic medication in Taiwan. METHODS: The IMS CORE Diabetes Model, a validated simulation model, was used to project health and economic outcomes for patients with T2DM treated with dulaglutide or liraglutide. Specific comparisons were: dulaglutide 1.5 mg vs liraglutide 1.8 mg; dulaglutide 1.5 mg vs liraglutide 1.2 mg; and dulaglutide 0.75 mg vs liraglutide 1.2 mg. The analyses were conducted under the Taiwanese payer perspective, capturing all relevant direct medical costs over a lifetime time horizon. Clinical safety and efficacy data were derived from a network meta‑analysis using randomized controlled clinical trial data, including those from the AWARD (Assessment of Weekly AdministRation of LY2189265 [dulaglutide] in Diabetes) clinical trial program. One-way sensitivity analyses (OWSA) and probabilistic sensitivity analyses (PSA) explored the model’s sensitivity to specific parameters and overall uncertainty. RESULTS: Under base case assumptions, dulaglutide 1.5 mg was found to be dominant (less costly and more effective) compared with liraglutide 1.8 mg. Dulaglutide 1.5 mg and 0.75 mg were also cost‑effective compared with liraglutide 1.2 mg, generating incremental costs per quality-adjusted life year of New Taiwan dollars in the range of 73,000 to 149,000. Results of the OWSA and PSA were consistent with base case results over a range of plausible input values. CONCLUSIONS: These results suggest that the introduction of once-weekly dulaglutide will be a cost-effective treatment option for patients with T2DM commencing injectable therapy in Taiwan.