AT AIBD 2016
ORLANDO (FRONTLINE MEDICAL NEWS) – The rapidly evolving field of biologic and biosimilar agents can leave gastroenterologists reeling in terms of what role biosimilars will play in practice and how best to utilize them for a patient with ulcerative colitis or Crohn’s disease. Limited data so far – primarily case series and limited postmarketing findings – suggest that a biosimilar can be as safe and effective as the innovator biologic. However, more rigorous research and more research overall are needed to confirm this comparative efficacy and to address unanswered questions around switching and cost effectiveness.
The uncertainty stems in part from a lack of prospective, randomized comparison studies to guide evidence-based clinical practice, Miguel D. Regueiro, MD , gastroenterologist and IBD clinical medical director at the University of Pittsburgh Medical Center.
“Why not stick with what we know and love?” Dr. Regueiro said, referring to the biologic agents widely regarded as very effective. The building momentum behind biosimilars is primarily driven by economics because “health care spending has grown faster than the rest of the economy in recent decades.” Also, if rigorous studies demonstrate true cost savings with biosimilars, that will in turn raise the question of whether or not pharmacies will be able to substitute a biosimilar for a prescribed biologic without the physician’s knowledge, Dr. Regueiro said at the Advances in Inflammatory Bowel Diseases meeting.
As clinicians await more definitive evidence, a number of limited studies have been published in the past year assessing biosimilars in inflammatory bowel disease (IBD). “The clinical response ranges were high, in most studies more than two-thirds [of patients] had a response, but again there are no head-to-head studies,” Dr. Regueiro said at the meeting sponsored by the Crohn’s & Colitis Foundation of America.
“We don’t have the data yet in IBD.”
A review of the literature on anti-tumor necrosis factor antibody biosimilar Inflectra (infliximab-dyyb, Celltrion) supports its bioequivalence to infliximab (Remicade, Janssen) in ankylosing spondylitis ( Aliment Pharmacol Ther. 2015;42:1158-69 ). However, dosing regimens and use of concomitant medications differ in the IBD population, the investigators noted, so the case series and short-duration postmarketing results published in the literature leave unanswered questions for gastroenterologists.
Just because biosimilars appear bioequivalent so far in IBD, it does not mean this new class of agents is free of controversy. When the U.S. Food and Drug Administration approved Inflectra in April 2016 based on evidence in ankylosing spondylitis and rheumatoid arthritis, it extrapolated the approval to all conditions for which infliximab is approved, including ulcerative colitis and Crohn’s disease. However, this “highly controversial approach has been criticized by various rheumatology and gastroenterology professional societies around the world,” according to authors of a critical review on biosimilars in IBD ( Inflamm Bowel Dis. 2016;22:2513-26 ).
Clinicians can safely switch patients from infliximab to Inflectra, according to the noninferiority phase IV NOR-SWITCH study conducted in Norway. Researchers assessed almost 500 patients on stable infliximab treatment for a minimum of 6 months prior to switching. However, this was a multi-indication study that included inflammatory bowel disease patients and many others, Dr. Regueiro said. “When you read the fine print in these studies, especially with Crohn’s disease, you start to see differences,” he added.
Although the evidence is encouraging so far, “we do not have prospective, comparative studies yet.”
During a Q&A panel session, a meeting attendee asked if clinicians will be able to use the same laboratory assay used to check a biologic’s drug and antibody levels for its biosimilar. “Our understanding is you will not be able to use the same assay as you do for infliximab. There are companies developing assays specifically for the biosimilars, and I think they will be available in addition to the ones for the innovator agents.”
