NEW YORK (Reuters Health)—Antibodies to infliximab in patients with inflammatory bowel disease (IBD) treated with Janssen’s Remicade cross-react with the biosimilar Remsima from Celltrion (distributed as Inflectra by Hospira in the U.S.), researchers from Israel report.
“The cross-reactivity of anti-Remicade antibodies with Remsima attests to shared immune triggering points (epitopes) on these two agents, and may therefore provide a further level of evidence to reassure physicians about the similarity between this particular biosimilar and the originator infliximab,” said Dr. Shomron Ben-Horin from Sackler School of Medicine, Tel-Aviv University in Ramat-Gan, Israel.
“The toll to pay for this similarity is that physicians should refrain from switching to Remsima (in) patients with anti-Remicade antibodies, especially if they have high-titer antibodies,” he told Reuters Health by e-mail.
In studies of rheumatoid arthritis and ankylosing spondylitis, rates of antidrug antibodies to Remicade and Remsima were similar, Dr. Ben-Horin’s team writes in Gut, online April 20.
But there have been no direct studies to investigate cross-immunogenicity of the two compounds, particularly in IBD patients, they add.
The researchers studied 86 patients to see if antibodies elicited by Remicade would cross-react with and recognize Remsima to a similar extent. None of the patients had ever been exposed to Remsima.
All sera that tested positive to anti-Remicade antibodies were also cross-reactive with Remsima, the team found. Conversely, all sera that tested negative to anti-Remicade antibodies were also negative for anti-Remsima antibodies.
In functional assays, anti-Remicade-positive sera inhibited Remicade and Remsima TNF-alpha binding to a similar extent, whereas anti-Remicade-negative sera inhibited neither Remicade nor Remsima TNF-alpha binding capacity.
Seven anti-adalimumab-positive sera from IBD patients never exposed to Remicade had no detectable anti-Remicade or anti-Remsima cross-reacting antibodies.
“These results suggest that these two infliximab monoclonal antibody drugs are similarly recognized by the immune system in patients with inflammatory bowel disease,” Dr. Ben-Horin said. “This implies that the rate of immunogenicity problems manifesting as loss of response or infusion reactions is probably not likely to be significantly different between Remicade or Remsima in clinical practice.”
“While these results are reassuring and in line with the findings of the head-to-head trials in rheumatoid arthritis and ankylosing spondylitis, pharmacovigilance studies are still warranted and are indeed ongoing to monitor the safety of this biosimilar in clinical practice,” he added.
Dr. Xavier Roblin from the department of gastroenterology at CHU Saint-Etienne, France, told Reuters Health by e-mail, “We must await interventional studies and long-term follow-up to conclude comparable safety and efficacy of biosimilar (drugs) in IBD patients.”
