How Severe Are Immunotherapy Adverse Events for Cancer and Preexisting Autoimmune Disease?
A recent study summarized the available evidence on adverse events associated with checkpoint inhibitors in patients with cancer and preexisting autoimmune disease, published in the Annals of Internal Medicine (online January 2, 2018; doi:10.7326/M17-2073).
Previous studies have shown that cancer immunotherapy with checkpoint inhibitors is associated with frequent immune-related adverse events and is often not recommended for patients with concomitant autoimmune diseases. However, the severity of such adverse events and whether they can be managed without discontinuing therapy has yet to be fully determined.
Noha Abdel-Wahab, MD, PhD, section of rheumatology and clinical immunology, department of general internal medicine, University of Texas MD, Anderson Cancer Center (Houston, TX), and colleagues attempted to summarize all of the available evidence on immuno-related adverse events in patients with cancer and preexisting autoimmune disease. Researchers searched MEDLINE, EMBASE, Web of Science, PubMed ePubs, and the Cochrane Central Register of Controlled Trials through September 2017 to identify original case reports, case series, and observation studies describing patients receiving checkpoint inhibitors for such concomitant diseases. Two reviewers independently extracted data and assessed the quality of reporting.
A total of 123 patients in 49 publications were identified. Among this sample, 75% (n = 92) had an exacerbation of preexisting autoimmune disease, immune-related adverse events, or both. Researchers noted that no differences in adverse events were determined in patients with active verses inactive disease.
Additionally, researchers acknowledged that patients receiving immunosuppressive therapy at initiation of checkpoint inhibitor therapy had fewer adverse events than those not receiving treatment. A majority of flares and immune-related adverse events were managed with corticosteroids, with 16% requiring other immunosuppressive therapies.
Importantly, researchers reported that adverse events were effectively managed and improved in over 50% of patients without discontinuation of checkpoint inhibitor therapy.
Results of the study led researchers to conclude that flares and immune-related adverse events in patients with autoimmune disease who are receiving checkpoint inhibitors can often be managed without discontinuing therapy. However, some adverse events may be severe and fatal; three patients died of adverse events in their analysis. “Prospective longitudinal studies are needed to establish incidence of adverse events and to evaluate risk-benefit ratios and patient preferences in this population,” they wrote.
Dr Abdel-Wahab and colleagues acknowledged a few limitations of their analysis, including the quality and quantity of data as well as the lack of prospective observational studies prohibiting incidence from being determined.—Zachary Bessette