Fecal bacterial and fungal microbiota composition are useful for estimating a patient’s response to treatment with infliximab for inflammatory bowel disease (IBD), according to the results of a study published in the Journal of Crohn’s & Colitis.
Infliximab, a tumor necrosis factor-alpha (TNF-α) blocker, is usually successful in treating IBD, although one-third of patients do not respond to therapy. Therefore, because there are no reliable biomarkers for predicting response to infliximab, researchers investigated fecal bacterial and fungal communities during infliximab therapy to identify predictors of an infliximab treatment response in patients with IBD.
The investigators identified 72 patients with IBD (25 with Crohn disease and 47 with ulcerative colitis) who started treatment with infliximab and were followed for 1 year or until treatment was discontinued. An amplicon sequencing approach targeting the bacterial 16S rRNA gene and fungal ITS 1 region separately was used to determine the microbiota profiles in fecal samples collected before the initiation of infliximab therapy and at 2 weeks, 6 weeks, 12 weeks, and 1 year after initiation of therapy. In addition, the response to treatment was evaluated by colonoscopy and clinically at 12 weeks after initiation.
The investigators found that both the fecal bacterial and fungal profiles differed significantly between response groups before the start of infliximab treatment. Nonresponders had a lower abundance of short-chain fatty acid producers, particularly of the class Clostridia, and higher abundance of proinflammatory bacteria and fungi, such as the genus Candida, compared with responders. This was further indicated by bacterial taxa predicting the response in patients with either Crohn disease or ulcerative colitis.
The authors concluded, “These results further strengthen previously published results that the gut microbiota could provide promising biomarkers for [infliximab] therapy response prediction in the future.”
Disclosure: Several study authors declared affiliations with the pharmaceutical industry. Please see the original reference for a full list of authors’ disclosures.
Ventin-Holmberg R, Eberl A, Saqib S, et al. Bacterial and fungal profiles as markers of infliximab drug response in inflammatory bowel disease. J Crohns Colitis. Published online December 10, 2020. doi:10.3390/cells8070719