Study of Spontaneous AE Reports Finds Signal for Infection With Reference, but Not Biosimilar, Infliximab

For inflammatory diseases, biosimilar infliximab CT-P13 (Inflectra, Remsima) has provided a more cost-effective option that has expanded access to biologic therapy in many nations, including Japan. The Japanese Adverse Drug Event Report (JADER) database, a large, published database managed by the Pharmaceuticals and Medical Devices Agency for pharmacovigilance, collects spontaneous reports as a means to detect adverse events (AEs) related to drugs, and a newly published study used the JADER data to assess AEs related to the reference infliximab and to the biosimilar.

In the study, published this month in the Journal of Pharmaceutical Health Care and Sciences, the researchers used data from 2014 (when the biosimilar launched in Japan) through 2018 and focused particularly on AEs related to infection. They identified 2771 reports of AEs (494 distinct events) related to the reference infliximab, and 402 reports of AEs (113 distinct events) related to the biosimilar.

Infection-related AEs accounted for 23.7% of reports for the reference infliximab and 21.9% of reports for the biosimilar. Among infection-related AEs associated with the reference, the most common was pneumonia, followed by interstitial lung disease, tuberculosis, and sepsis. Among infection-related AEs associated with the biosimilar, the most commonly reported AEs were pneumonia, followed by interstitial lung disease and sepsis.

Interestingly, write the authors, the reporting odds ratio (ROR) for infection with the biosimilar was 1.48 (95% CI, 0.7-3.13), while the ROR for infection with the reference drug was 3.54 (95% CI, 2.93-4.29); thus, the biosimilar was not associated with infection, while a signal was detected for the reference infliximab.

According to the authors, this observation may be because AE reporting was limited for the biosimilar versus the reference. If reports increase over time, the conclusion may also change, so more studies are warranted. The study was also limited by the fact that JADER data do not allow calculations for true incidence rates, and the fact that ROR does not provide a robust indication of signal strength.

“It is recommended that research be continued in order to accumulate a wide variety of information, and that newly reported data be placed in the multifaceted viewpoints for improvement of care levels,” write the authors.

Reference

Niinomi I, Hoshohata K, Mori Y, et al. Evaluation of adverse events focusing on infection associated with infliximab originator and biosimilar using a spontaneous reporting system database. J Pharm Health Care Sci. 2019;7(5):21. doi: 10.1186/s40780-019-0149-z.