REFILE-Nivolumab-ipilimumab combo appear helpful in biliary-tract cancers

Last Updated: 2020-08-05

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By David Douglas

NEW YORK (Reuters Health) - In patients with advanced biliary-tract cancers, combination immunotherapy with nivolumab and ipilimumab shows promising activity, according to a new study.

Chemotherapy is the standard treatment for all patients with advanced biliary-tract cancers, resulting in only modest survival benefit, Dr. Oliver Klein of Olivia Newton-John Cancer Centre, Austin Hospital, in Heidelberg, Australia, and colleagues note in JAMA Oncology.

"The main implication of our study finding is that combination immunotherapy with dual checkpoint inhibition can lead to durable responses in a significant subset of patients with advanced biliary-tract cancers; a tumor type that has so far been seen as fairly unresponsive/ refractory to immunotherapy," Dr. Klein told Reuters Health by email.

Immunotherapy using anti-programmed cell death protein 1 (PD-1) therapy has shown limited activity in such patients. However, immunotherapy using combined anti-PD-1 and anticytotoxic T-lymphocyte-associated protein 4 (CTLA-4) blockade with nivolumab and ipilimumab has shown promise in certain tumor types.

To investigate further, the researchers studied data from a prospective multicenter phase-2 nonrandomized clinical trial of patients with advanced rare cancers, including biliary-tract cancers.

The researchers identified 39 patients with biliary-tract cancer, most of whom had experienced disease progression after at least one line of therapy. Their mean age was 65 years and all had tumor tissue available for biomarker research.

Patients received nivolumab 3 mg/kg and ipilimumab 1 mg/kg every three weeks for a total of four doses. This was followed by nivolumab 3 mg/kg every two weeks. In the absence of disease progression or the development of unacceptable toxic events, this was continued for up to 96 weeks.

A fifth of patients experienced rapid disease progression after enrollment and received only one or two treatment doses.

An objective response was seen in nine patients (23%), and disease control was seen in 17 (44%). All responders had received prior chemotherapy, and none had a microsatellite-unstable tumor.

"The promising activity suggests that this combination may be the preferred immunotherapy regimen for further study in biliary tract cancers," the researches write.

Responses were observed only in patients with intrahepatic cholangiocarcinoma and gallbladder carcinoma. This suggests, say the researchers, that response to dual checkpoint-inhibitor therapy in biliary-tract cancers may differ by anatomical site.

The median duration of response (ranging from 2.5 to more than 23 months) was not reached. The median progression-free survival was 2.9 months and overall survival was 5.7 months.

Half of the patients experienced immune-related toxic events, with 15% experiencing grade-3 or -4 events. There were no treatment-related deaths.

Bristol-Myers Squibb provided funding and study drugs for the research. Dr. Klein and several coauthors report financial ties to the company.

SOURCE: https://bit.ly/2Xnk1oT JAMA Oncology, online July 30, 2020.