Infliximab Biosimilar Found to Be Safe, Effective

Routine infliximab (IFX) biosimilar SB2 therapy was observed to be safe and effective in IFX-naïve patients and in patients changed from a prior IFX reference or biosimilar, according to a study published in Rheumatology Advances in Practice.

The PERFUSE study was conducted to evaluate the 12-month persistence, effectiveness, and safety effects of routine SB2 treatment in patients who have chronic inflammatory rheumatic disease.

“The marketing authorization of SB2 was based on demonstration of comparable physicochemical and biological characteristics, pharmacokinetic similarity in healthy patients, and comparable efficacy and safety in patients with RA [rheumatoid arthritis] compared with IFX ref,” said the researchers.

The PERFUSE trial was a noninterventional study of 1233 adult patients (rheumatology, n = 496; irritable bowel disease, n = 737) receiving periodic IFX biosimilar SB2 therapy.

First, patients with a diagnosis of RA, psoriatic arthritis, or axial spondyloarthritis (axSpA) were accredited to 1 of 3 study cohorts according to whether SB2 treatment started after September 2017 had been the first IFX treatment (IFX naïve) or followed a shift from reference IFX (IFX ref) or another IFX biosimilar (IFX bs). Effects to month 12 (mean [SD] value 2) was composed of persistence (primary outcome), SB2 dose, disease status, immunogenicity, and safety.

During month 12, persistence on SB2 in the IFX-naïve, IFX ref, and IFX bs cohorts, respectively, consisted of the following 59% (95% CI, 36.1%-76.2%), 75% (95% CI, 57.5%-86.1%), and 85% (95% CI, 69.6%-93.0%) for RA (n = 98); 64% (95% CI, 34.3%-83.3%), 87% (95% CI, 65.6%-95.7%), and 83% (95% CI, 60.0%-93.1%) for PsA (n = 62); and 56% (95% CI, 44.4%-66.5%), 80% (95% CI, 70.8%-86.1%), and 80% (95% CI, 72.5%-85.6%) for axSpA (n = 336).

Disease activity was commensurate at baseline and month 12 in both the IFX ref and bs subgroups of all cohorts by indication. No concerns of immunogenicity and new safety signals were detected. In addition, during the 12-month time period, the last month from the PERFUSE study rheumatology cohorts showed no clinically meaningful differences in clinical effectiveness during a 12-month period in patients switched from IFX ref or IFX bs to SB2.

“More than 75% of patients who transitioned from prior IFX and continued on SB2 treatment to month 12 post SB2 initiation showed no meaningful difference in clinical measures, regardless of whether they received prior IFX ref or IFX bs. More than 56% of IFX-naïve patients continued on SB2 treatment at month 12 with no changes in dosing regimen,” said the researchers.

In the PERFUSE study, the persistence rate was seen to be aligned with the reported persistence rate for biosimilar CT-P13, as well as the discontinuation rate communicated for patients started on IFX ref, indicating that although a nocebo effect can’t be ruled out, this did not have a meaningful impact in the studied population.

Following this, the researchers said, “In PERFUSE, the most frequent reason for discontinuation was physician decision following loss of response.”

Since concerns remain for some prescribers about switching to biosimilars, the researchers determined that it’s important to review immunogenicity data in the real-world setting. Even though routine immunogenicity testing was sporadic in the study population, the results did not show an increased risk of immunogenicity to IFX after SB2 initiation.

The authors described no increased risk of immunogenicity as a result of 1 switch or successive switches to IFX bs, which confirm PERFUSE timing so far.

Some limitations of this study include the small sample size and that no patient control groups were present of patients staying on reference or other IFX bs because all eligible patients had been moved to SB2.

“Long-term studies and real-world studies using SB2 for the treatment of patients with chronic inflammatory rheumatic diseases will increase our understanding of the clinical utility of biosimilars and their potential to pave the way for increased access to treatment,” concluded the researchers.

Reference

Fautrel B, Bouhnik Y, Dieude P, et al. Real-world evidence of the use of the infliximab biosimilar SB2: data from the PERFUSE study. Rheumatol Adv Pract. Published online April 17, 2023. doi:10.1093/rap/rkad031