IBD PATIENTS IN remission CAN SAFELY SWITCH TO INFLIXIMAB BIOSIMILAR
April 12, 2018
By Marilynn Larkin
NEW YORK (Reuters Health) - Switching to CT-P13, an infliximab biosimilar, is safe and well tolerated in patients with IBD whose disease is in remission, researchers say.
"Biological treatment of chronic inflammatory diseases has improved patient outcomes but increased health care costs," Dr. Anne Strik of Academic Medical Center in Amsterdam and colleagues noted in their report online March 29 in The Lancet Gastroenterology and Hepatology. "Switching patients from originator infliximab to a biosimilar can reduce costs, but prospective data about pharmacokinetics and potential immunogenicity are scarce."
To investigate, Strik's team conducted a noninferiority trial at 13 sites in Belgium and the Netherlands in 46 patients with ulcerative colitis (UC) and 42 with Crohn's disease (CD).
In the UC group, the mean age was 48.3 years; 46% were male; and median disease duration was 9 years. In the CD group, the mean age was 41.5; 52% were male, and the median disease duration was 10 years.
Patients were switched from originator infliximab to CT-P13 at a dose and infusion duration identical to those of the originator (i.e., approximately 5 mg/kg every 7 to 9 weeks). After switching, patients were followed up for 16 weeks.
Serum concentrations of infliximab were measured at baseline (before the first dose of CT-P13), 8 weeks, and 16 weeks.
The geometric mean ratio of serum infliximab concentrations at week 16 (CT-P13) compared with those at baseline (originator) was 110.1% (90% CI 96.0–126.3) in patients with UC and 107.6% (97.4–118.8) in those with CD.
In both groups of patients, the lower bound of the 90% CI was higher than the prespecified non-inferiority margin of 85%, meaning that serum concentrations of infliximab after switching to CT-P13 were non-inferior to concentrations of the originator infliximab in this patient population.
Six serious adverse events were reported in six patients. Only one of these adverse events, a perianal abscess, was judged to be related to study treatment.
"This trial was performed in patients in clinical remission, which is important to keep in mind while discussing extrapolation of results or making a . . . statement concerning switching the entire IBD population," Dr. Strik told Reuters Health by email.
"Currently, we are working on a Cochrane review about switching IBD patients from the originator to CT-P13," she added. "After gathering all available literature and looking at all the results, more definitive advice about switching IBD patients can be given."
Dr. Richard Bloomfeld, director of IBD Services at Wake Forest Baptist Medical Center in Winston-Salem, North Carolina, told Reuters Health, "Although the U.S. Food and Drug Administration tells us that 'a biosimilar is a biologic product that is highly similar to and has no clinically meaningful differences from an existing FDA-approved reference product,' physicians and patients may still have some concerns about using biosimilars."
