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.
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.
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.
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 (
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.
No outside funding supported this study. Farraye reports advisory board fees from Janssen, Merck, and Pfizer. Shah reports speaker fees from Pfizer. The other authors have nothing to disclose.