November 2022: For adult patients with locally advanced or metastatic biliary tract cancer, the Food and Drug Administration has approved durvalumab (Imfinzi, AstraZeneca UK Limited) in combination with gemcitabine and cisplatin (BTC).
The effectiveness of TOPAZ-1 (NCT03875235), a multiregional, randomised, double-blind, placebo-controlled trial that enrolled 685 patients with histologically confirmed locally advanced, unresectable, or metastatic BTC but who had not previously received systemic therapy for advanced disease, was assessed.
The following were the trial’s racial and gender breakdowns: 50% male and 50% female; median age 64 years (range 20-85); and 47% of participants were 65 years or older. In addition to gallbladder cancer and extrahepatic cholangiocarcinoma, 56 percent of patients also had intrahepatic cholangiocarcinoma.
Patients were assigned at random to receive:
Durvalumab 1,500 mg on day 1, plus gemcitabine 1,000 mg/m2 and cisplatin 25 mg/m2 on days 1 and 8 of each 21-day cycle up to 8 cycles, then 1,500 mg of durvalumab every four weeks, or
Placebo on Day 1+ followed by placebo every four weeks, followed by gemcitabine 1,000 mg/m2 and cisplatin 25 mg/m2 on Days 1 and 8 of each 21-day cycle up to 8 cycles.
Until the disease progressed or the side effects became intolerable, durvalumab or a placebo was continued. If the patient was clinically stable and reaping a clinical benefit, as evaluated by the investigator, treatment was permitted beyond disease progression.
The primary effectiveness outcome was overall survival (OS). For the first 24 weeks, tumour assessments were made every 6 weeks; after that, they were made every 8 weeks, until objective disease progression was proven. Individuals who were randomly assigned to receive durvalumab with gemcitabine and cisplatin showed a statistically significant improvement in OS compared to patients who were randomly assigned to receive placebo with gemcitabine and cisplatin. In the durvalumab and placebo groups, the median OS was 12.8 months (95% CI: 11.1, 14) and 11.5 months (95% CI: 10.1, 12.5), respectively (hazard ratio 0.80; 95% CI: 0.66, 0.97; p=0.021). In the durvalumab and placebo groups, the median progression-free survival was 7.2 months (95% CI: 6.7, 7.4) and 5.7 months (95% CI: 5.6, 6.7), respectively. In the durvalumab and placebo arms, the investigator-assessed overall response rates were 27% (95% CI: 22% – 32%) and 19% (95% CI: 15% – 23%), respectively.
The most frequent adverse events experienced by patients (20%) were pyrexia, lethargy, nausea, constipation, decreased appetite, and gastrointestinal pain.
When combined with gemcitabine and cisplatin, the recommended dose of durvalumab is 1,500 mg every three weeks for patients with a body weight under 30 kg, followed by 1,500 mg every four weeks as a single agent until disease progression or intolerable toxicity. The recommended dose for individuals with a body weight of less than 30 kg is 20 mg/kg every three weeks with gemcitabine and cisplatin, followed by 20 mg/kg every four weeks until the disease progresses or there is intolerable toxicity.
