AstraZeneca Combination Treatment Helps Advanced Biliary Tract Cancer

AstraZeneca recently announced that Imfinzi combined with standard-of-care chemotherapy significantly improved overall survival and progression-free survival in patients with advanced biliary tract cancer (BTC).

The randomized Phase 3 trial, TOPAZ-1, enrolled 685 patients with unresectable advanced or metastatic BTC, including intrahepatic and extrahepatic cholangiocarcinoma and gallbladder cancer, to receive Imfinzi in combination with chemotherapy as first-line treatment.

In the study, patients who received the combination treatment experienced a 20 percent reduction in the risk of death versus chemotherapy alone.

The median overall survival for these patients was 12.8 months versus 11.5 months for chemotherapy alone. And about 25 percent of patients were still alive at two years, compared to 10 percent of patients who just received chemotherapy.

Additionally, researchers found a 25 percent reduction in risk of disease progression or death with Imfinzi plus chemotherapy. Median progression-free survival was 7.2 months for the combination versus 5.7 months for chemotherapy alone.

Patients treated with the combination treatment also saw an objective response rate (ORR) of 26.7 percent versus an ORR of 18.7 percent for patients treated with just chemotherapy.  

“The results from the TOPAZ-1 trial challenge treatment expectations in advanced biliary tract cancer and provide compelling evidence that longer-term survival is possible,” Susan Galbraith, executive vice president of oncology research and development at AstraZeneca, said in the announcement.

“This is a potential new standard of care for patients in this setting and we remain committed to making advances in gastrointestinal cancers with high unmet need,” Galbraith continued.

Notably, researchers found that Imfinzi plus chemotherapy did not increase the discontinuation rate due to adverse events compared to chemotherapy alone.

About 62.7 percent of patients who received the combination treatment experienced Grade 3 or 4 adverse events, compared to 64.9 percent of patients receiving chemotherapy alone. Treatment-related adverse events led to the discontinuation of 8.9 percent of patients treated with Imfinzi and chemotherapy versus 11.4 percent of patients receiving just chemotherapy.

In December 2020, the US granted Imfinzi orphan drug designation to treat BTC.

Do-Youn Oh, MD, PhD, professor, division of medical oncology in the department of internal medicine at Seoul National University Hospital and Seoul National University College of Medicine, and principal investigator in the trial, emphasized that the combination treatment will provide a needed and potentially practice-changing new treatment option in a setting where the current prognosis is “devastating.”