Flares of preexisting rheumatic diseases
These tend to occur much earlier in the course of immune checkpoint inhibitor therapy for cancer than de novo immunotherapy-related rheumatic adverse events. In a retrospective Australian study of 12 cancer patients with preexisting rheumatic disease before going on a PD-1 inhibitor and 24 others with no such history, all of whom developed rheumatic adverse events while on the checkpoint inhibitor, the mean time to a flare of preexisting rheumatic disease was 6.2 weeks, compared to 21.5 weeks in patients who experienced a de novo rheumatic adverse event.
Dr. Ruderman supports recommendations from the European Alliance of Associations for Rheumatology (EULAR) for the management of rheumatic immune-related adverse events due to cancer immunotherapy, even though the underlying level of evidence is fairly weak. The recommendations call for the use of csDMARDs when corticosteroids don’t adequately control symptoms. And when the response to csDMARDs is insufficient, the next step is a biologic, preferably a tumor necrosis factor inhibitor or interleukin-6 inhibitor.
“At our institution, the oncologists are a little bit nervous about using biologics in cancer patients, but I think more and more they’re going to have to accept it. And so far there isn’t a ton of evidence that suggests the addition of biologics interferes with the efficacy of the immunotherapy,” the rheumatologist said.
He underscored the critical importance of one of the overarching principles of the EULAR guidelines: the need for interdisciplinary coordination between rheumatologists and oncologists regarding the problem of rheumatologic immune-related adverse events.
“Oncologists aren’t good at managing inflammatory arthritis. I think they really need us,” he said.
Dr. Ruderman reported serving as a consultant to and/or receiving a research grant from nine pharmaceutical companies.