NEW YORK (Reuters Health)—About two-thirds of patients with ulcerative colitis (UC) had mucosal healing by the end of induction treatment with the infliximab biosimilar CT-P13, according to results of the first prospective study to evaluate this.
CT-P13 is the first biosimilar monoclonal antibody of reference infliximab (Remicade) approved in Europe and several other countries where it is known as Remsima. An advisory committee to the U.S. Food and Drug Administration endorsed it, and the FDA approved the treatment in April. But until now, data on the effect of CT-P13 on mucosal healing were lacking.
To investigate, Dr. Tamas Molnar of University of Szeged in Hungary and colleagues studied 63 UC patients (mean age 30, mean disease duration 5.7 years) who received CT-P13 induction therapy at three IBD clinics in Hungary and one in the Czech Republic. Reasons for starting CT-P13 included acute, severe flare up and chronic, refractory activity.
CT-P13 induction consisted of 5 mg/kg given as an intravenous infusion at Weeks 0, 2 and 6 followed by a maintenance regimen of 5 mg/kg every eight weeks, except for one Czech patient with acute severe disease who received an induction dose of 10 mg/kg.
At baseline, the mean value of total Mayo score was 9.2, with mean endoscopic subscore (eMayo) of 2.7 points at the beginning of the CT-P13 therapy.
At Week 14, the mean value of total Mayo score dropped to 3.4, with eMayo of 1.1. Both scores decreased significantly in responders at Week 14 compared with baseline (p<0.001 and p<0.001)
The cumulative clinical response rate was 82.5%. Steroids could be tapered and stopped in 60% of the patients on systemic corticosteroids at entry.
At Week 14, sigmoidoscopy showed mucosal healing in 38 patients (60.3%), the authors report. Thirty patients (47.6%) had steroid-free mucosal healing. Complete mucosal healing (eMayo of 0) was achieved in 17 (27%) patients. Trough levels of CT-P13 correlated with mucosal healing.
“Infliximab biosimilar CT-P13 represents a promising treatment option for patients with UC not only regarding clinical activity, but also in achieving mucosal healing,” the authors conclude in their paper, online on April 21 in the Journal of Crohn’s and Colitis.
In a related paper in the journal, online on April 19, Dr. Lisa Smits from Radboud University Medical Centre and colleagues report short-term clinical outcomes following a switch from brand name infliximab to CT-P13 in a “real-life” cohort of 83 patients with inflammatory bowel disease.
The primary endpoint was disease activity at week 16 after switching to CT-P13 relative to baseline. Secondary endpoints included additional inflammatory, pharmacokinetic and immunogenicity parameters, as well as quality of life and safety. All markers were assessed at Week 0 and 16.
“Switching did not result in significant changes of disease activity as corroborated by relevant and validated biomarkers,” Dr. Smits and colleagues report. “Pharmacokinetic parameters such as [trough level] of CT-P13 were maintained during the study. Two patients developed new detectable [antidrug antibodies] and [five] patients discontinued CT-P13.” There were no unexpected safety signals.
The design of the study, which did not include a control group that allowed patients to continue brand name infliximab, is a limitation of the study, they note. “Therefore, it is difficult to interpret changes in efficacy, safety and pharmacokinetics that may be due to either the switch to CT-P13 or may be coincident with the natural course. The ongoing NOR-SWITCH study (estimated completion date January 2017) might be able to provide answers to some of the issues,” they write.
They note that the cohort was heterogeneous in terms of diagnosis, infusion schedule and disease activity. “As such our cohort reflects real world practice outside the strict in- and exclusion criteria of randomized controlled trials, which allows immediate translation of results to clinical care. However, the duration of follow-up was relatively short and longer follow-up is required to determine long-term efficacy, safety and immunogenicity of CT-P13.
Despite these limitations, the authors say their study shows that switching from brand name infliximab to CT-P13 had no marked impact on short-term clinical outcomes, suggesting that making the switch to CT-P13 for the treatment of IBD is “feasible.”
None of the studies had commercial funding and the authors did not report relevant conflicts of interest.
