The combination of the PD-1 inhibitor Opdivo (nivolumab) and the CTLA-4 inhibitor Yervoy (ipilimumab) has been effective therapy for some types of solid tumor cancers, such as melanoma and lung cancer. In the clinical trial reported at the 2020 ASCO annual meeting, researchers evaluated the effectiveness of these 2 immunotherapies together in patients with metastatic (spreading) cholangiocarcinoma (CCA). The study’s lead author was Oliver Klein, FRACP, MD, Olivia Newton-John Cancer Research Institute, Heidelberg, Australia.
Patients received this combination every 3 weeks for 4 doses, then every 2 weeks for up to 96 weeks, until disease progression or unacceptable side effects. A total of 85% of the patients had received at least 1 previous line of chemotherapy. None of the patients who had a response to therapy had tumors with microsatellite instability, a type of genetic alteration.
Among all the patients, 24% had a complete response (no sign of cancer) or a partial response to therapy, and 44% of the patients had either tumor shrinkage or stable disease.
The duration of the response to therapy ranged from 2 months to more than 26 months, and the average duration of response was not yet reached by the time of this report. Responses to the combination therapy were seen in 31% of patients with intrahepatic CCA, 10% of patients with extrahepatic CCA, and 31% of patients with gallbladder cancer.
In addition, 2 patients who had a partial response to therapy subsequently had surgery to remove the tumor and were rendered free of disease. The average time of survival without disease progression (getting worse) was 2.9 months, and the overall survival was 5.7 months.
A total of 56% of patients had immune-related side effects, and 17% of patients had serious (grade 3 or 4) side effects.
The researchers concluded that the combination of nivolumab and ipilimumab was significantly beneficial to patients with microsatellite-stable tumors.