Inflammatory bowel disease is treated with anti-TNF agents such as infliximab and its biosimilars, but use of biosimilars is limited due to perceived risks of adverse events.
To explore safety and effectiveness of switching from the infliximab originator to a first biosimilar.
Clinical and biological outcomes were compared between 53 patients who switched from the infliximab originator to the biosimilar CT-P13 (Switched group) and 13 patients treated with CT-P13 from the beginning (Naïve group). Infliximab trough levels and antidrug antibodies were measured.
At enrolment, patients in the Switched group had a longer median duration of infliximab treatment than Naïve (4.0 vs. 0.6 years, p < 0.0001) but similar proportions of patients were in remission (77% and 62%, respectively). Infliximab discontinuation due to adverse events or loss of efficacy was less common in the Switched (26%) than Naïve group (62%, p = 0.017). Variables independently associated with time to discontinuation were disease activity (p < 0.0001) and immunomodulating treatment (p = 0.019) at enrolment. Trough levels and antidrug antibodies were similar between groups during observation.
This study confirms that switching from infliximab originator to a first biosimilar is safe and effective. Patients at highest risk of losing treatment efficacy are those with active disease, irrespective of the therapeutic switch.