On September 2, 2022, the FDA approved Imfinzi (durvalumab; from AstraZeneca), a PD-L1 inhibitor, for use in combination with chemotherapy, for the treatment of adults with locally advanced or metastatic (spreading) biliary tract cancer, a type of gastrointestinal (GI) cancer.
“This approval represents a major step forward for patients with advanced biliary tract cancer, who urgently need new, well-tolerated and effective treatment options after more than a decade of limited innovation,” said Aiwu Ruth He, MD, PhD, Associate Professor of Medicine and Leader of the GI Cancer Program, Georgetown Lombardi Comprehensive Cancer Center, Medstar Georgetown University Hospital, Washington, DC.
“The combination of durvalumab and chemotherapy should become a new standard of care in this setting, having demonstrated significantly improved survival for these patients who have historically faced a poor prognosis,” Dr. Ruth He added.
The FDA approved this new indication of Imfinzi based on results of a randomized, placebo-controlled clinical trial that included 685 patients with locally advanced, unresectable (can’t be removed by surgery) or metastatic biliary tract cancer (including 56% of patients with intrahepatic cholangiocarcinoma, 25% of patients with gallbladder cancer, and 19% with extrahepatic cholangiocarcinoma).
The patients were divided into 2 groups to receive either Imfinzi plus chemotherapy or placebo plus chemotherapy; the treatment continued until their disease progressed or they had unacceptable side effects. The average time of survival was 12.8 months in patients who received Imfinzi plus chemotherapy compared with 11.5 months in patients who received placebo plus chemotherapy. The average time without disease progression was 7.2 months with Imfinzi plus chemotherapy and 5.7 months with placebo plus chemotherapy.
Most important, 27% of the patients who received Imfinzi plus chemotherapy responded to treatment compared with only 19% of the patients who received placebo plus chemotherapy, a significant difference in terms of patients whose tumor responded to therapy.
The most common side effects reported in 20% or more of the patients receiving Imfinzi in this study were fatigue, nausea, constipation, decreased appetite, abdominal pain, rash, and pyrexia.