Patients with rheumatoid arthritis who were using rituximab at the time of COVID-19 onset had a fourfold higher risk of being hospitalized, needing mechanical ventilation, or dying, compared with patients taking a tumor necrosis factor inhibitor (TNFi), according to a report given at the annual European Congress of Rheumatology.
The use of Janus kinase inhibitors (JAKi) also was associated with a twofold higher risk for these COVID-19 outcomes, said Jeffrey A. Sparks, MD, of Brigham and Women’s Hospital and Harvard Medical School, Boston, in presenting the analysis from the COVID-19 Global Rheumatology Alliance (GRA) Physician Registry.
“The strong association of rituximab and JAK inhibitor use with poor COVID-19 outcomes highlights the prioritization of risk mitigation strategies for these patients,” Sparks said at the meeting.
The full findings have now been published in Annals of the Rheumatic Diseases.
JAKi Association Questioned
These findings provide “an important understanding for the risk of our patients in times before vaccination,” said Hendrik Schulze-Koops, MD, of Ludwig Maximilian University of Munich, who chaired the session in which the study was presented. However, “recently, baricitinib was licensed to prevent particular aspects of severe COVID. What’s the explanation for this discrepancy?” he asked.
“Certainly, the JAK inhibitor finding deserves further study,” Sparks acknowledged, adding that the data were analyzed by class rather than for individual drugs.
“One possible explanation could be when JAK inhibitors are used,” he suggested. “It might be different for patients who [have been] just infected — that might have different biologic effects — as opposed to choosing to treat patients right when there’s a hyperinflammatory cascade, or there’s oxygen need.”
Regarding the JAK inhibitor finding, Ronald van Vollenhoven, MD, PhD, of the University of Amsterdam, pointed out during the online Q&A that “JAKi have a very short half-life compared to biologics.”
Van Vollenhoven asked: “Could the practice of stopping these drugs upon COVID infection have a negative impact on the course?” To which Sparks responded: “The different half-life of drugs would be a promising avenue to look at, to see whether increases in disease activity might have imparted some of the effects we saw.”
Performing the Analysis
As of April 12, 2021, the GRA Physician Registry contained the records of more than 15,000 patients. Sparks, collaborator Zachary Wallace, MD, of Massachusetts General Hospital, Boston, and associates limited their analysis to 2,869 patients with RA who had been treated with either a biologic or targeted synthetic disease-modifying antirheumatic drug (b/tsDMARD) at the time they were diagnosed with COVID-19.
“We wanted to limit it to a single disease and also limit it to drugs that are considered for that disease,” Sparks explained in an interview.
“Because patients with rheumatoid arthritis are often treated sequentially, we wanted to further limit the analysis to patients who were on advanced therapies so that they were at a similar disease state, and also had the opportunity to receive advanced therapies.”
This approach hopefully minimizes the possibility of confounding by indication, Sparks said.
Most of the patients included in the analysis had received a TNFi (n = 1,388), and they were used as the control arm of the analysis. Outcomes associated with treatment with the other b/tsDMARDs, which included abatacept (n = 237), rituximab (n = 364), interleukin-6 inhibitors (IL-6i; n = 317), and JAKi (n = 563), were then compared with TNFi.
Baseline characteristics of patients were broadly similar across the groups. The mean age was 56.7 years and 80.8% of the study population was female. There were a few expected differences among users of rituximab versus TNFi, notably a higher percentage of patients with interstitial lung disease (11% vs. 1.4% of TNFi users) or cancer (7.4% vs. 0.9%) among patients treated with rituximab since it is commonly used in these patients, Sparks said.
“We did perform a sensitivity analysis where we restricted the population to not having ILD or cancer and we actually found really similar findings,” he added.
Four COVID-19 Outcomes Assessed
The researchers used a four-point ordinal scale modeled after one set by the World Health Organization to assess four COVID-19 outcomes: not hospitalized, hospitalized without oxygenation, hospitalized with oxygenation or ventilation, and death.
Odds ratios (ORs) comparing rituximab to TNFi for these four COVID-19 outcomes were a respective 4.53, 2.87, 4.05, and 4.57. The ORs for JAKi versus TNFi were a respective 2.4, 1.55, 2.03, and 2.04.
“We found no consistent associations of abatacept or interleukin-6 inhibitors with COVID-19 severity, compared to TNF inhibitors,” which is reassuring, Sparks said.
ORs for the four COVID-19 outcomes with abatacept were a respective 1.18, 1.12, 1.41, and 1.46, and for IL-6i were 0.84, 0.72, 0.75, and 1.13.
Rituximab Use in Patients With RA Who Develop COVID-19
So, should rituximab be stopped in patients with RA if they develop COVID-19? “This is an important question and one that would be decided on a case-by-case basis,” Sparks said. “Of course, the drug has a very long half-life, so risk mitigation strategies are still of utmost importance,” he added.
“I think everyone’s a bit reticent to want to start rituximab in this environment, but it might also make me pause about starting a JAK inhibitor,” Sparks added. “Given that this is a first finding, I’m not sure I would necessarily change patients who are doing well on these medications. I think what it really makes me want to do is to try to obviously vaccinate the patients on JAK inhibitors as they do have a short half-life.”
More observational studies would be helpful, Sparks said, adding that “the most pressing need is to try to figure out how to protect our patients with rituximab.”
The COVID-19 Global Rheumatology Alliance Physician Registry is supported by the American College of Rheumatology and the European Alliance of Associations for Rheumatology. Sparks disclosed serving as a consultant for Bristol-Myers Squibb, Gilead, Inova, Optum, and Pfizer for work unrelated to this study. Wallace disclosed receiving grant support from Bristol-Myers Squibb and Principia/Sanofi and serving as a consultant for Viela Bio and Medpace for work unrelated to this study.
This article originally appeared on MDedge.com, part of the Medscape Professional Network.