Process and Clinical Outcomes of a Biosimilar Adoption Program with Infliximab-Dyyb

BACKGROUND: In 2016, the FDA approved infliximab-dyyb (IFX-dyyb) as a biosimilar to infliximab (IFX). Deemed to have comparable efficacy and safety to IFX, IFX-dyyb is 20%-30% less expensive, allowing significant cost savings for institutions and some payers. In 2018, IFX was reported to be the drug with the highest spend since 2013, costing $3.8 billion; however, transition to IFX-dyyb would save $1.1 billion. Regardless, many institutions have not transitioned to IFX-dyyb or other IFX biosimilars (e.g., IFX-abda) because of concerns about clinical outcomes, uncertainty regarding financial impact, and barriers to operationalizing biosimilar adoption. At Boston Medical Center, a decision was made in March 2018 to adopt IFX-dyyb and transition patients who have been on IFX for ≥ 6 months for all indications to IFX-dyyb. OBJECTIVES: To (a) describe a biosimilar adoption process of IFX-dyyb in patients on IFX for ≥ 6 months; (b) characterize cost savings of transitioning patients to IFX-dyyb; and (c) evaluate real-world clinical outcomes of adult patients with inflammatory bowel disease (IBD) who transitioned to IFX-dyyb. METHODS: This is a retrospective cohort study of patients eligible for the IFX-dyyb switch from March 2018 to June 2019 at a large academic medical center. For process outcomes, we collected the proportion of patients who transitioned to IFX-dyyb and calculated the cost savings generated. To assess clinical outcomes of adult IBD patients who transitioned, we collected IFX and IFX-dyyb dosage, Harvey Bradshaw Index (HBI) or Simple Clinical Colitis Activity Index (SCCAI) scores, c-reactive protein (CRP) levels, and colonoscopy results. Descriptive statistics, Wilcoxon signed-rank test, and McNemar’s test were used for statistical analyses. RESULTS: Of 151 eligible patients, 146 (97%) successfully transitioned to IFX-dyyb. Based on our conversion rate to IFX-dyyb, our health system is forecasted to save approximately $500,000 annually. From March to June 2018, 63 of 75 (84%) eligible IBD patients transitioned from IFX to IFX-dyyb. In this cohort, of the 40 patients with HBI or SCCAI scores before and after transition, 36 (90%) maintained remission. For 32 patients, the mean CRP (SD) before transition was 11.2 (22) and 4.1 (4.8) after transition (P = 0.09). Since the IFX-dyyb transition, 9 patients had a colonoscopy, of which 5 (56%) were in endoscopic remission. As of October 2018, 56 (89%) patients continued with IFX-dyyb after transition. Of the 46 patients who had 12-15 months posttransition data, 38 (83%) remained on IFX-dyyb. CONCLUSIONS: Implementation of a biosimilar adoption program can be successful and result in significant cost savings without compromising clinical outcomes. A model that uses actionable strategies and embraces collaboration among stakeholders is described here, with outcomes demonstrating successful IFX-dyyb uptake and no changes in clinical outcomes of transitioned adult patients with IBD.