Switching Among Multiple Infliximab Biosimilars Does Not Cause Immunogenicity, Study Finds

A new study has found that switching among multiple biosimilar infliximab products was not associated with increased immunogenicity in patients with inflammatory diseases.

The study, presented at the European League Against Rheumatism European Congress of Rheumatology 2019, was conducted at a single center in France.¹

The study’s prospective cohort included 265 patients, 135 of whom had axial spondyloarthritis, 64 of whom had inflammatory bowel disease, 31 of whom had rheumatoid arthritis, 21 of whom had psoriatic arthritis, 8 of whom had uveitis, and 6 of whom had other inflammatory diseases.

These patients were all treated with the reference infliximab, then were switched to a biosimilar and followed for 3 years. Prior to the switch, 29 patients had antidrug antibodies (ADAs).

Later, at year 2, 140 patients were switched to a second biosimilar infliximab, while 26 remained on the first biosimilar and 55 patients switched back to the reference product. Among the 236 patients with no ADAs before the first switch occurred, 20 developed ADAs during the observation period, corresponding to a rate of 3 per 100 patient years. The mean (SD) time to ADA detection was 21.2 (13.7) months.

Kaplan—Meier analysis showed that the number of biosimilars received did not impact development of ADAs. Among the 20 patients who developed new ADAs, 4 were taking the reference product at the time of detection, while 10 had been exposed to the first biosimilar only, and 6 had been exposed to both biosimilars.

No predictive factors, including age, disease state, sex, body mass index, or concomitant drug therapy, were identified for immunogenicity.

The retention rate for biosimilar infliximab was 58% at the end of the observation period, including 131 patients treated with the second biosimilar and 23 patients treated with the first biosimilar.

According to the authors, “immunogenicity does not constitute a barrier to interchangeability between biosimilars infliximab in chronic inflammatory diseases.”

These results are a notable addition to the literature on switching among biosimilars of the same reference drug; switching among multiple products is increasingly common in countries where single-winner tenders for biosimilars are undertaken and in which patients may be asked to transition among products regularly based on the outcome of the tendering process. Increased immunogenicity has been a stated concern among some physicians who question the practice of nonmedical switching among products, and these real-world data may provide reassurance that such switches do not pose a problem with respect to increased immunogenicity.

These results follow those of another study, also conducted in France, in which 21 patients with psoriatic arthritis were switched from one biosimilar infliximab to another, then followed for 6 months.² In this study, investigators found that the switch between the biosimilars was not associated with a statistically significant change in disease activity or with increased adverse events.

References

1. Lauret A, Moltó A, Abitbol V, et al. Effects of successive switches to different biosimilars infliximab on immunogenicity in chronic inflammatory diseases in daily clinical practice. Presented at: The European League Against Rheumatism European Congress of Rheumatology 2019, June 12-15, 2019; Madrid, Spain. Abstract OP0227.

2. Gisondi P, Virga C, Girolomoni G. Cross-switch from CT-P13 to sb2 infliximab biosimilars in patients with chronic plaque psoriasis. Presented at: 6th Congress of Skin Inflammation and Psoriasis International Network; April 25-27, 2019; Paris, France. Abstract P049.