In a phase 2 clinical trial, 2 different combinations were studied and compared for use as the first treatments given to patients with cholangiocarcinoma (CCA).
Group A received the PD-1 inhibitor Opdivo (nivolumab) plus chemotherapy with gemcitabine and cisplatin. Group B received the same PD-1 inhibitor (nivolumab) with the CTLA-4 inhibitor Yervoy (ipilimumab).
The lead investigator of the study, Vaibhav Sahai, MBBS, MS, Leader, Gastrointestinal Medical Oncology Section, University of Michigan, Ann Arbor, presented the study results at the 2020 ASCO annual meeting.
Overall, 64% of patients in group A, who received the PD-1 inhibitor plus chemotherapy, had 6-month survival without disease progression (getting worse); by contrast, only 23% of the patients in group B, who received the PD-1 plus CTLA-4 inhibitors, had 6-month survival without disease progression.
The average time of survival without disease progression was 7.4 months with PD-1 plus chemotherapy and 4.1 months with PD-1 plus CTLA-4. The average overall survival was 10.6 months with the PD-1 inhibitor plus chemotherapy and 8.3 months with the PD-1 plus CTLA-4 inhibitors.
The time of progression-free survival with the 2 immunotherapies (PD-1 plus CTLA-4 inhibitors) was lower than with current therapies. By contrast, treatment with a PD-1 inhibitor plus chemotherapy is as effective as standard-care chemotherapy.
Overall, 40% of the patients receiving PD-1 plus chemotherapy are still alive, indicating that there may be a potential extension of survival. We do not yet have complete results of safety and side effects, as well as overall response rate and other measurements.
Although group A (PD-1 inhibitor plus chemotherapy) was not superior to standard chemotherapy, there are currently 2 phase 3 clinical trials of PD-1 inhibitor plus chemotherapy combinations that are recruiting patients for further study.