For successful switching of bio-originators to biosimilars, confidence in the switch is an important criterion. To promote confidence, scientific evidence is critical, but still there are insufficient data for the majority of approved biosimilars. Areas covered: Scientific evidence for switching from bio-originator DMARDs to biosimilars is derived from randomized controlled trials (RCTs) for switching, extension studies of RCTs for the approval process, and real-world observational studies. To identify candidate studies, PubMed was searched to collect appropriate studies in all approved biosimilars for the treatment of rheumatic diseases. In addition, abstracts for scientific meetings were reviewed to discover abstracts focused on switching. To date, we have identified 17 extension studies of RCTs, 1 RCT, and 17 real-world observational studies. Most real-world studies have originated from CT-P13 and SB4. Switching was definitively safe and effective in most of studies, but some nocebo effects were observed. Expert commentary: Clear guidelines for switching and data from post-marketing surveillance and registries will be required to confirm existing results on the safety and efficacy of switching from bio-originators to biosimilars. To lessen the nocebo effect against biosimilars, effective educational programs should be provided for all stakeholders, including patients and physicians.
Keywords: Biosimilars; education; nocebo effect; randomized controlled study; switching.