An analysis of the Phoenix cohort provides insight into responder rates and treatment persistence with infliximab biosimilars among those with no previous exposure to biologics, a previous failure to respond to biologics, or those switching from reference infliximab.
Data from an analysis of patients receiving treatment at a trio of hospitals over a 5-year period suggests infliximab biosimilars were effective for inducing clinic remission in patients with inflammatory bowel disease (IBD).
A retrospective cohort study of patients with ulcerative colitis (UC) or Crohn disease (CD) receiving treatment with infliximab biosimilars, results of the study provides clinicians with insight into the effects of infliximab biosimilars for UC and CD, with results detailing the impacts among those considered biologic-naive, those with previous biologic failures, and those switching from an originator to a biosimilar.1
“The present study showed that [infliximab biosimilars] are as effective and safe as [infliximab] originators even with long-term administration. In addition to the favorable remission induction in the bio-naïve and bio-failure groups, we demonstrated the remission maintenance and treatment persistence rates beyond two years after treatment,” wrote investigators.1
With its first approval from the US Food and Drug Administration coming in 1998, infliximab boasts indications for multiple conditions, including Crohn disease, ulcerative colitis, rheumatoid arthritis, ankylosing spondylitis, psoriatic arthritis, and chronic severe plaque psoriasis.2 In the current study, a team of investigators led by Hiroshi Nakase, MD, PhD, professor and chair of the Department of Gastroenterology and Hepatology at Sapporo Medical University School of Medicine, sought to examine the long-term effectiveness and safety profile of infliximab biosimilars as well as to identify factors associated with treatment persistence rate in patients with IBD using data from the Principal research in Hokkaido Organization Emphasizing Nutritional and therapeutic Improvement to IBD patients’ eXpectation cohort (Phoenix) cohort.1
Comprised of individuals who received treatment at Sapporo Medical University Hospital, Asahikawa Medical University Hospital, and Sapporo Higashi Tokushukai Hospital, investigators identified 117 people who received infliximab biosimilar at these sites between October 2016 and April 2022 for inclusion. Of these 117, 90 patients had CD and 27 had UC.1
Among those with CD, 17 were in the bio-naïve group, 3 were in the bio-failure group, and 70 were in the switch group. The overall cohort of CD patients had a median age of 45 (interquartile range, 37-53.5), 73.3% were male, and the median age at disease onset was 25 (IQR, 19-31) years. Among those with UC, 14 were in the bio-naïve group, 7 were in the bio-failure group, and 6 were in the switch group. The overall cohort of UC patients had a median age of 49 (IQR, 29-65) years, 63% were male, and the median age at disease onset was 34 (IQR, 20-53) years.1
The primary outcome of interest for the trial was the achievement of clinic remission, which was assessed using the Crohn’s disease activity index (CDAI) and the partial Mayo (pMayo) score for the CD and UC cohorts, respectively. Clinical remission of CD was a CDAI less than 150 points and clinical remission of UC was a pMayo score of 2 or fewer. Secondary outcomes of interest for the study included persistency of long-term infliximab biosimilar administration and clinical response rate in those considered bio-naïve and those considered bio-failures.1
Upon analysis, results suggested both bio-naïve and bio-failure groups of patients with UC showed similar effectiveness of infliximab biosimilars. Among patients with UC, the percentages of responders in the bio-naïve and bio-failure groups at 54 weeks were 60% and 42.9% respectively.1
When assessing treatment persistence, results suggested greater treatment persistence was observed among the switch group than among the bio-naïve group among people with UC.1
In the CD group, the proportion of responders at 8 weeks were 81.8%, 0%, and 97% in the bio-naïve, bio-failure, and switch groups. When assessing treatment persistence, investigators observed a significantly greater persistence rate in patients with CD among the bio-naïve (P = .042) and switch (P = .010) groups than in the bio-failure group, with a treatment persistence rate of more than 80% in both the bio-naïve and switch groups.1
Additional univariable and multivariable analyses for treatment persistence suggested albumin level at the initial infliximab biosimilar administration and groups were considered effective factors for patients with CD. Investigators also pointed out adverse events were recorded among 15.4% of those using infliximab biosimilars.1
“This is the first retrospective cohort study to investigate the long-term effectiveness and safety of [infliximab biosimilars] beyond five years in Japanese patients with IBD with respect to clinical practice. We found that the effectiveness of remission induction and maintenance by [infliximab biosimilars] was comparable to that by infliximab originator,” investigators concluded.1