Recent studies have demonstrated the effectiveness and safety of infliximab biosimilars in patients with IBD, but there are limited data about the effectiveness and safety of switching from infliximab to CT-P13 in these patients.
Dr. Maria Chaparro of the University Hospital La Princesa, in Madrid, Spain and colleagues evaluated outcomes of IBD in their retrospective study of 277 patients who continued taking infliximab versus 199 patients treated at centers that switched from infliximab to CT-P13 as a general practice for all their patients.
During a median follow-up of 18 months in the switch group and 23 months in the continuation group, the incidence of clinical relapse was significantly higher in the switch group (14% per patient-year) than in the continuation group (5% per patient-year).
The cumulative incidences of relapse in the CT-P13 group were 5% at six months, 14% at 12 months and 28% at 24 months, compared with 2%, 4% and 10%, respectively, in the continuation group.
In multivariate analysis, switching from infliximab to CT-P13 was the only factor significantly associated with higher risk of relapse (hazard ratio, 3.5), the researchers report in the Journal of Crohn’s and Colitis, online April 12.
Median C-reactive protein (CRP) concentrations did not differ between the groups at baseline or at the end of follow-up, although CRP concentrations were higher at the end of follow-up in patients who relapsed than in those who continued in remission.
The proportion of patients experiencing adverse events was significantly higher in the continuation group (13%) than in the switching group (6%).
The researchers attribute the higher clinical relapse rate in the face of similar CRP concentrations after switching to CT-P13 to a possible nocebo effect resulting from concerns of patients and physicians about the safety and efficacy of biosimilar agents.
“The introduction of biosimilar agents as a treatment option for IBD patients could achieve substantial cost saving for health care systems,” they note. “However, given the significant impact that nocebo effects can have on patients’ quality of life and health services, it is important to develop interventions to minimize the appearance of these effects.”
“With new biosimilar agents entering the market in the near future, specific programs based on gain share agreements should be developed to ensure that all stakeholders are convinced and motivated to accept the switch with the consequent benefits to the patients and the health system,” the authors conclude.