Adverse events related to immune checkpoint inhibitor (ICI) therapy lack alternative treatments outside of glucocorticoids, which themselves may reduce the efficacy of ICI therapy in patients with cancer. Researchers in the COLAR trial examined whether interleukin-6 blockade with tocilizumab reduced ICI-induced colitis and arthritis and concluded that tocilizumab had promising efficacy and manageable safety profiles for this population.
The clinical trial, published in the Journal for Immunotherapy of Cancer, enrolled 20 patients. Participants had solid cancers and met Common Terminology Criteria for Adverse Events (CTCAE) for grade >1 ICI-induced colitis/diarrhea (n=9), arthritis (n=9), or both (n=2).
Tocilizumab Improves ICI-Induced Colitis and Arthritis
Patients’ ICI treatments included pembrolizumab (n=10), nivolumab (n=4), or combined ipilimumab and nivolumab (n=5), and tocilizumab was administered at 8 mg/kg every 4 weeks. The primary end point of the study was improvement in colitis or arthritis.A total of 19 patients were included in the final analysis after 1 exclusion due to pancreatic insufficiency-induced diarrhea.
According to the researchers, 15 out of 19 (79%) patients achieved the primary end point of a 1 or greater reduction in CTCAE score within 8 weeks. One further patient achieved the primary end point at week 10, and one other maintained stable symptoms. Additionally, at week 24, 12 patients had ongoing improvement without glucocorticoids and 10 had complete remissions of ICI-induced colitis or arthritis.
In closing, the authors summarized that that tocilizumab demonstrated promising efficacy with manageable toxicity in patients with ICI-induced colitis and arthritis (84% clinical benefit rate), and highlighted that half of their patients were able to continue ICI treatment alongside tocilizumab.
“Further studies are required to confirm these results and to eventually compare efficacy of tocilizumab with currently standard approaches in the treatment of ICI-induced toxicities,” the researchers closed.