Immune Checkpoint Inhibitor-Associated Inflammatory Arthritis Can Last Months

A majority of patients who developed inflammatory arthritis associated with the use of immune checkpoint inhibitors continued to experience the condition months after ceasing the cancer-fighting agents, according to a study published in the March 2020 issue of the Annals of the Rheumatic Diseases.

“While immune checkpoint inhibitors have improved overall survival and cancer progression-free duration, they can be associated with various autoimmune and inflammatory syndromes known as immune-related adverse events,” the researchers said. “Some immune-related adverse events, such as colitis and pneumonitis, can be life-threatening, while others such as inflammatory arthritis can have a dramatic impact on quality of life.”

The prospective observational study monitored 60 patients diagnosed with immune checkpoint inhibitor-induced inflammatory arthritis. At their last follow-up visit, which varied from 1 month to 24 months after immune checkpoint inhibitor cessation (the median was 9 months), 53.3% of participants still had inflammatory arthritis. The rate of patients with active inflammatory arthritis at 3 months after immune checkpoint inhibitor cessation was 70.6%. At 6 months, the rate was 48.8%.

Factors associated with inflammatory arthritis persistence were the use of combination immune checkpoint inhibitor therapy, longer duration of exposure to immune checkpoint inhibitors, and the development other immune-related adverse events, according to the study.

Immunomodulatory treatments for inflammatory arthritis were effective for symptom control and did not appear to affect tumor response.

“Interestingly, our data suggest that the development of persistent arthritis may associate with better antitumor responses compared with patients who have transient inflammatory arthritis,” the researchers wrote. “This could reflect ongoing activation of the immune system that portends better antitumor immunity.” —Jolynn Tumolo

Reference

Braaten TJ, Brahmer JR, Forde PM, et al. Immune checkpoint inhibitor-induced inflammatory arthritis persists after immunotherapy cessation. Annals of the Rheumatic Diseases. 2020;79(3):332-33. doi:10.1136/annrheumdis-2019-216109