Infliximab biosimilar CT-P13 is interchangeable with its originator for patients with inflammatory bowel disease in real world practice.

Background/aims: An interim analysis of post-marketing surveillance of CT-P13, an infliximab biosimilar, was performed to evaluate its safety and efficacy in Japanese patients with inflammatory bowel disease.

Methods: Patients were prospectively enrolled between November 2014 and March 2017, after the launch of CT-P13 in Japan, and case report forms of patients followed for at least 4 months were analyzed as of July 2018.

Results: Of 523 patients in the analysis set, 372 remained on CT-P13 therapy, while 54 (20.2%) of 267 patients with Crohn's disease, and 97 (37.9%) of 256 patients with ulcerative colitis were withdrawn during follow-up. A total of 144 adverse drug reactions (ADRs) were reported in 106 patients (20.3%). Infusion reaction was the most frequent ADR observed in 49 patients (9.4%). Efficacy parameters decreased immediately after the start of treatment in naïve patients to anti-tumor necrosis factor-α antibody. In the patients switched from originator infliximab for nonmedical reasons, the decreased parameters due to proceeded treatment with the originator were maintained in low ranges, and the treatment continuation rate was high with low ADR incidence. In contrast, in patients switched for medical reasons such as adverse event or loss of response, the incidence of ADRs was high. However, the efficacy parameters were improved, and the treatment continuation rate was not significantly different from that of the naïve patient group.

Conclusions: In this interim analysis, CT-P13 was comparable to the originator infliximab with respect to ADRs and efficacy, and is therefore considered to be a cost-efficient interchangeable biosimilar for Japanese patients with inflammatory bowel disease.