Patients with rheumatoid arthritis treated with tofacitinib (Xeljanz) were 69% less likely to develop interstitial lung disease (ILD), compared with those treated with adalimumab (Humira), according to a new retrospective study.
About 10% of RA patients develop ILD, but data on how different biologic and targeted synthetic disease-modifying antirheumatic drugs (b/tsDMARDs) may affect the risk of developing ILD is lacking, the authors wrote. Identifying treatments that may have protective effects could be useful when prescribing treatments for patients with RA who are at higher risk for ILD, first author Matthew C. Baker, MD, clinical chief in the division of immunology and rheumatology at Stanford (Calif.) University, said in an interview.
In the analysis, published in JAMA Network Open researchers used the Optum Clinformatics Data Mart to identify claims data for patients with RA who were taking b/tsDMARDs from December 2003 to December 2019. Patients were excluded if they had a preexisting diagnosis of ILD or if they had less than 1 year of continuous enrollment in the data set.
The researchers identified 28,559 patients with RA who were treated with adalimumab (13,326), abatacept (Orencia; 5,676), rituximab (Rituxan; 5,444), tocilizumab (Actemra; 2,548), and tofacitinib (1,565). More than three-fourths of patients were female (78%), and their average age was 55.6 years old. During the study period, 276 developed ILD. An adjusted model showed a 69% lower incidence of ILD in patients treated with tofacitinib, compared with those treated with adalimumab (adjusted hazard ratio, 0.31; 95% confidence interval, 0.12-0.78; P = .009). An additional sensitivity analysis also showed a similar reduction in ILD risk in those taking tofacitinib, compared with adalimumab (aHR, 0.32; 95% CI, 0.13-0.82; P < .001). There was no significant difference in risk of developing ILD in the abatacept, rituximab, or tocilizumab groups, compared with the adalimumab group.
“Patients who generally looked similar with RA, but were given different treatments, had different risks of developing ILD,” Dr. Baker said. “Based on what we found, most of the biologic therapies had similar rates of developing ILD, but the JAK inhibitor tofacitinib had a reduced risk.” Additional research is necessary to see if tofacitinib shows the same benefit in prospective studies, he said.
“Even though this wasn’t a clinical trial, it suggested that one of the medications that we use to treat RA could potentially prevent the development of ILD,” Elizabeth Volkmann, MD, codirector of the Connective Tissue Disease-Related Interstitial Lung Disease Program at the University of California, Los Angeles, told this news organization. She was not involved with the study.
With retrospective studies, it is difficult to account for all confounding factors, even with adjusted models, she said. For example, the authors did not have data on patients’ history of smoking, a known risk factor for ILD that could have affected which treatment was selected, they acknowledged. The tofacitinib group was also smaller than other treatment groups, which “may have contributed to a small number of events,” the authors wrote. “However, the follow-up time was similar across all groups, and we used Cox proportional hazard models to investigate the association between time-to-event and use of treatment while controlling for the other baseline characteristics.”
Both Dr. Baker and Dr. Volkmann agreed that future research could also investigate whether tofacitinib prevents the progression of ILD in patients with RA who already have the lung condition. “That’s never been looked at before,” Dr. Volkmann said.
Dr. Baker and a coauthor received support for this work from grants from the National Institutes of Health. Dr. Baker and Dr. Volkmann report no relevant financial relationships.
A version of this article first appeared on Medscape.com.