Clinical application
Dr. Taneja said the findings of the study are novel and intriguing. “The observations suggest a strong influence of [the] host’s microbiome in response to MTX and in future may inform best treatment options for patients. The study speculates that certain microbial clades or microbes can be used to derive a favorable response in patients. This could explain why “one drug fits all” does not apply in treatment for RA,” she said.
The study is also a “step forward” in using the microbiome in regular clinical practice, she noted. “Since MTX is used as a first line of treatment and is one of the most affordable treatments for RA, the observations are definitely exciting.”
Dr. Martin Kriegel
In an interview, Martin Kriegel, MD, PhD, of the department of immunobiology at Yale University, New Haven, Conn., and chair of rheumatology and clinical immunology at the University of Münster (Germany), explained that the prediction model has the potential to one day be a tool for clinicians to predict MTX response in patients with RA. However, he noted the researchers did not test a functional link between MTX and gut microbes in vivo.
“It would be useful to test mechanistic effects of MTX on gut microbial communities in vitro and in vivo,” he said. “In addition, it would be informative to apply the prediction model in other cohorts of RA with a different geographic background, possibly also a different duration of disease. If confirmed in a more heterogeneous group of patients, the tool could potentially be used in the clinic to tell some patients that they might not respond to MTX and therefore start therapy with another agent.”
This study was funded by the National Institutes of Health, the Rheumatology Research Foundation, the Searle Scholars Program, various funds from the Spanish government, the UCSF Breakthrough Program for Rheumatoid Arthritis-related Research, and the Arthritis Foundation Center for Excellence. Four authors report consultancies and memberships on scientific advisory boards with pharmaceutical and biotechnology companies that do not overlap with the current study.
Dr. Taneja reported that her institution holds a patent for developing Prevotella histicola as an anti-inflammatory treatment, of which she is a coinventor. Evelo Biosciences is a licensee for the patent, and Dr. Taneja reported receiving research support from the company. Dr. Kriegel reported receiving salary, consulting fees, honoraria, or research funds from AbbVie, Bristol-Myers Squibb, Cell Applications, Eligo Bioscience, and Roche. He also holds a patent on the use of antibiotics and commensal vaccination to treat autoimmunity.
SOURCE: Artacho A et al. Arthritis Rheumatol. 2020 Dec 13. doi: 10.1002/art.41622.