For the first time, new-onset connective tissue disease has been reported in patients who were treated with anti-PD1/PDL-1 agents, according to findings published in the Annals of the Rheumatic Diseases.
In a cohort of 447 cancer patients who received therapy with immune checkpoint inhibitors (ICIs), Sébastien Le Burel, MD, of the Bicêtre Hospital in Le Kremlin-Bicêtre, France, and his colleagues described four patients who developed a connective tissue disease (CTD). There were two cases of Sjögren’s syndrome in patients taking an anti–programmed cell death 1 (anti-PD1) drug, one case of cryoglobulinemic vasculitis as a complication of suspected Sjögren’s syndrome in a patient taking an anti–programmed cell death ligand 1 (PDL-1) agent, and a case of a patient with antinuclear antibody positive myositis who was taking an anti-PDL-1 drug (Ann Rheum Dis. 2017 Feb 27. doi: 10.1136/annrheumdis-2016-210820).
“While the onset of systemic autoimmune disease after ICI treatment remains uncommon, greater awareness of these conditions should enable physicians to provide more effective patient care,” the investigators wrote. “This underlines the need for close collaboration within a network of oncologists and other specialist physicians in the new era of immunotherapy.”
The investigators discovered the cases by screening the French prospective, multicenter, academic REISAMIC registry for reports of CTD among patients being treated with anti-PD1 or anti-PDL-1 agents.
All four of the patients who developed a CTD had metastatic cancer, and their mean age was 62 years. Two patients had been treated with anti-PD1 agents and two with anti-PDL-1 agents. None of the four patients had presented with symptoms of CTD before they began treatment.
The mean time interval between the first treatment dose and the first symptom of CTD was 60 days (range, 24-72), and the mean time interval between the first symptom and subsequent diagnosis of CTD was 40 days (range, 10-74).
Three patients discontinued the ICI agent, and two patients were treated with steroids (1 mg/kg/day).
The estimated prevalence of CTD was 0.7% in the REISAMIC registry, and the authors emphasize that the high proportion of cases of Sjögren’s syndrome is noteworthy, with two of the patients fulfilling the recent American College of Rheumatology/European League Against Rheumatism criteria for Sjögren’s syndrome.
A limitation of the study is that some patients presenting with milder symptoms might not have been investigated by their oncologist.
The findings raise the question of whether asymptomatic patients taking ICIs who are at risk for immune-related adverse events should be screened and monitored closely, the authors explained.
One of the study authors received research funding from Novartis and Pfizer for the current paper. Several authors report relationships with industry.