Using pembrolizumab plus gemcitabine and cisplatin improves overall survival compared to chemotherapy alone in advanced biliary tract cancer
Patients with biliary tract cancers invariably present at a late stage when curative surgery is not possible. The current treatment for advanced biliary cancer involves chemotherapy with cisplatin plus gemcitabine and which improves survival. However, other work suggests that cisplatin treatment together with PD-1/PD-L1 blockade could increase the clinical response, particularly in lung cancer. In addition, treating advanced biliary cancer with pembrolizumab alone provides a small, but durable anti-tumour activity. However, one study with the PD-L1 inhibitor, durvalumab in advanced biliary tract cancer with cisplatin chemotherapy, showed good efficacy and an acceptable safety profile.
Researchers in the current study, sought to assess whether pembrolizumab plus cisplatin and gemcitabine chemotherapy might improve overall survival in advanced biliary tract cancer. Their randomised, placebo-controlled trial involved adult patients with previously untreated, unresectable, locally advanced or metastatic biliary tract cancer. Adults were randomised 1:1 to pembrolizumab plus chemotherapy or placebo and chemotherapy. The primary outcome was overall survival whereas the secondary outcome explored safety.
Pembrolizumab plus chemotherapy and overall survival
There were 1069 participants of whom, 533 had pembrolizumab followed for 25.6 months. Median overall survival was 12·7 months with pembrolizumab plus chemotherapy and 10·9 months in the placebo group (hazard ratio, HR = 0·83, 95% CI 0·72 – 0·95, p = 0.0034).
A similar proportion of pembrolizumab and placebo patients had treatment-related adverse events with a maximum grade of 3 to 4 (70% vs 69%). However, death due to adverse events was slightly less with pembrolizumab (6% vs 9%).
Kelly KR et al. Pembrolizumab in combination with gemcitabine and cisplatin compared with gemcitabine and cisplatin alone for patients with advanced biliary tract cancer (KEYNOTE-966): a randomised, double-blind, placebo-controlled, phase 3 trial. Lancet 2023