Patients with an underlying rheumatic disease, including Sjogren’s syndrome, are not at higher risk for adverse effects when receiving cancer immunotherapies – called immune checkpoint inhibitors – than the rest of the population, according to the results of a Mayo Clinic study.
The report, “Cancer immunotherapy in patients with preexisting rheumatologic disease: the Mayo Clinic experience,” appeared in the journal Arthritis & Rheumatology.
Immune checkpoint inhibitors have gathered increasing interest as cancer immunotherapy since its introduction in 2011. The therapy targets proteins at the surface of immune cells, which work as “switch-off” signs that hamper the immune system’s ability to detect cancer cells.
However, a pitfall of immune checkpoint inhibitors therapy is their potential for causing autoimmune reactions – collectively called immune-related adverse effects.
While the rate of these immune-related adverse effects is low in the general population – about 2 percent – its frequency in patients with rheumatologic diseases is unknown.
Researchers determined the risk of flare and adverse effects in patients with rheumatologic diseases treated with checkpoint inhibitor therapy. They reviewed the medical record of patients who received the immunotherapy at Mayo Clinic, Rochester, Minnesota, between 2011 and 2016.
The retrospective analysis identified 16 patients with rheumatologic diseases – the most common included rheumatoid arthritis (five patients), polymyalgia rheumatic (five patients), Sjogren’s syndrome (two patients), and systemic lupus erythematosus (two patients).
Patients had either malignant melanoma (10 patients), pulmonary malignancies (four patients), or non-Hodgkin lymphoma (two patients). Immune checkpoint inhibitors, which included Opdivo (nivolumab), Keytruda (pembrolizumab), or Yervoy (ipilimumab), were given only after they failed to respond to other types of cancer therapy.
After initiating cancer immunotherapy, 37.5 percent of the patients (six out of 16) developed immune-related adverse effects, which included temporal arteritis flare, colitis, intersticial pneumonitis, and hypophysitis.
“Every [immune-related adverse effect] was treated successfully with glucocorticoids and discontinuation of [immune checkpoint inhibitors] therapy,” researchers wrote.
Moroever, researchers detected no link between disease-modifying anti-rheumatic drug (DMARD) use – before or during immune checkpoint inhibitors therapy – and the risk for developing immune-related adverse effect. Ten patients (63 percent) had received prior treatment with DMARD but only two of them were being treated actively when they began cancer immunotherapy.
Overall, “based on our observations, immune checkpoint inhibitor therapy should be considered in select patients with pre-existing rheumatologic disease,” study lead author Uma Thanarajasingam, MD, PhD, of the Mayo Clinic, said in a press release.
“However, there is an immediate and pressing need for prospective, and ideally multi-center trials to study rheumatic patients who go on to need immune checkpoint inhibitor therapy — both to better understand their safety profile in this under-studied patient group, as well as elucidate risk factors and biomarkers for the development of immune-related adverse effects,” added Thanarajasingam.