After AstraZeneca’s Imfinzi last year claimed new territory in the biliary tract cancer space, Merck’s Keytruda has hit the scene with an FDA nod to match its rival.
The approval in locally advanced unresectable or metastatic biliary tract cancer, combined with the chemotherapies gemcitabine and cisplatin, marks Keytruda’s sixth U.S. nod in gastrointestinal cancer, Merck said.
The FDA based the approval on data from the company’s Phase 3 KEYNOTE-966 trial, which showed that the Keytruda-chemo combo extended patients' survival time compared with chemotherapy alone.
In the study, patients in the treatment arm lived a median 12.7 months, compared to 10.9 months for those on solo chemo. The Keytruda-chemo combo reduced the risk of death by 17% over solo chemotherapy, researchers found.
In addition, Keytruda-treated patients experienced a longer median duration of response at 9.7 months, compared with 6.9 months for solo chemotherapy.
Merck is “proud” to offer the new treatment option for biliary tract patients, many of whom are not eligible for surgery and face “poor survival outcomes with limited treatment options,” Merck's head of late-stage oncology clinical development, Marjorie Green, M.D., said in a statement.
Biliary tract cancers are a set of rare and “highly aggressive” cancers in the liver, gallbladder and bile ducts. Approximately 70% of patients are diagnosed at an advanced stage, where the five-year relative survival rate is just 2% to 3%, according to Merck.
The survival rate across all stages of biliary tract cancers stands at only 9% to 11%, according to the drugmaker.
When stacked up against Imfinzi’s TOPAZ-1 trial, Keytruda’s survival result just about matched Imfinizi’s 12.8 months.
However, Keytruda missed the mark on disease progression or death in its study, showing a 14% reduction. Imfinzi passed on that endpoint in its own study with a 25% reduction.
The studies enrolled different trial populations. KEYNOTE-966 enrolled a greater proportion of patients outside Asia, meaning its results “might be more representative of the global population,” two researchers at the Royal Marsden Hospital in the U.K. wrote in a commentary when the study results were published.

https://www.fiercepharma.com/pharma/mercks-keytruda-chalks-fda-win-biliary-tract-cancer-catching-astrazenecas-imfinzi