BACKGROUND: Data on nonmedical switching from one anti-Tumor Necrosis Factor (TNF)-α biosimilar to another in inflammatory bowel disease (IBD) are relatively sparse. We aimed to study the effects of nonmedical switch from infliximab biosimilar CT-P13 to SB2 and from adalimumab biosimilar ABP 501 to SB5. METHODS: In this observational study, consecutive IBD patients receiving nonmedical switch were prospectively followed-up for 12 months. The primary outcome was treatment persistence
other outcomes included: secondary effectiveness outcomes, safety, immunogenicity, inflammatory makers levels and psychometric assessments. RESULTS: A total of 119 and 76 patients were enrolled in the SB2 and SB5 cohorts. Persistence on treatment at 12 months was 84.0 % in the SB2 cohort and 78.9 % in the SB5 cohort. No clinically meaningful changes in other secondary effectiveness outcomes were recorded. Rates of 0.38 and 0.63 adverse events of interest per 100 patient-years were observed in the SB2 and SB5 cohorts. The pharmacokinetics and immunogenicity of either drug were unaffected by nonmedical switch
similarly, levels of inflammatory cytokines remained largely unchanged. No changes in psychometric assessments were recorded. CONCLUSION: Nonmedical switch of infliximab and adalimumab biosimilars does not significantly affect treatment effectiveness, safety and pharmacokinetics, nor does it have major psychological implications for patients.