Abstract Purpose We retrospectively compared 2 strategies for adalimumab biosimilar conversion at an academic medical center to better understand the effects of each strategy. Methods The formulary for our institution is managed by physician- and pharmacist-led task forces, in collaboration with our specialty pharmacy and pharmacy benefit manager. We implemented 2 phased strategies to increase adalimumab biosimilar utilization. First, we added preferred biosimilars to the formulary at parity to reference product and relied on prescribers to promote conversion. Second, we added an interchangeable biosimilar and removed reference product from the formulary while leveraging specialty pharmacy workflows for prescription conversions, streamlined facility inventory, and minimized dependence on prescriber workflows. For both strategies, we evaluated prescribing trends, dispensing data, and pharmaceutical spend for all medical center patients, specialty pharmacy patients, and patients with the top 3 specialty pharmacy payers. Results During phase 1 (quarter [Q] 2 of 2023 [2Q23] to 1Q24), reference product dispensing remained largely unchanged (<5% reduction). Phase 2 (2Q24 to 2Q25) resulted in a significant reduction in specialty pharmacy dispenses of reference product, from 95.7% to 19.0%. This phase also resulted in a 76.0% reduction in medical center adalimumab/biosimilar spend. At the end of phase 2, biosimilar accounted for 42.6% of all medical center patient prescriptions. Total dispensed units of reference product/biosimilar were modestly decreased (6%) during phase 2. Conclusion Formulary and clinical support for adalimumab biosimilar alone did not promote use over the reference product, but rapid and substantial biosimilar uptake was achieved after operational barriers were addressed.