On 2 September 2022, the US Food and Drug Administration (FDA) approved durvalumab (Imfinzi, AstraZeneca UK Limited) in combination with gemcitabine and cisplatin for adult patients with locally advanced or metastatic biliary tract cancer (BTC).
Efficacy was evaluated in TOPAZ-1 (NCT03875235), a randomised, double-blind, placebo-controlled, multiregional study that enrolled 685 patients with histologically confirmed locally advanced unresectable or metastatic BTC who had not previously received systemic treatment for advanced disease.
Study demographics were as follows: 56% Asian, 37% White, 2% Black, and 4% other race; 7% Hispanic or Latino; 50% male and 50% female; median age was 64 years (range 20-85) and 47% were 65 years or older. Fifty-six percent had intrahepatic cholangiocarcinoma, 25% had gallbladder cancer, and 19% had extrahepatic cholangiocarcinoma.
Patients were randomised 1:1 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, followed by durvalumab 1,500 mg every 4 weeks, or
- placebo 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, followed by placebo every 4 weeks.
Durvalumab or placebo were continued until disease progression or unacceptable toxicity. Treatment was permitted beyond disease progression if the patient was clinically stable and deriving clinical benefit, as determined by the investigator.
The major efficacy outcome measure was overall survival (OS). Tumour assessments were conducted every 6 weeks for the first 24 weeks, then every 8 weeks until confirmed objective disease progression. A statistically significant improvement in OS was demonstrated in patients randomised to receive durvalumab with gemcitabine and cisplatin compared to those randomised to receive placebo with gemcitabine and cisplatin. Median OS was 12.8 months (95% confidence interval [CI] 11.1, 14) and 11.5 months (95% CI 10.1, 12.5) in the durvalumab and placebo arms, respectively (hazard ratio 0.80; 95% CI 0.66, 0.97, p = 0.021). 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) in the durvalumab and placebo arms, respectively. Investigator-assessed overall response rate was 27% (95% CI 22% – 32%) and 19% (95% CI 15%-23%) in the durvalumab and placebo arms, respectively.
The most common (≥ 20%) adverse reactions occurring in patients were fatigue, nausea, constipation, decreased appetite, abdominal pain, rash, and pyrexia.
The recommended durvalumab dose is 1,500 mg every 3 weeks for patients with a body weight ≥ 30 kg when given with gemcitabine and cisplatin, followed by 1,500 mg every 4 weeks as a single agent until disease progression or unacceptable toxicity. For patients with a body weight < 30 kg, the recommended dose is 20 mg/kg every 3 weeks with gemcitabine and cisplatin followed by 20 mg/kg every 4 weeks until disease progression or unacceptable toxicity.
Full prescribing information for Imfinzi is available here.
This review was conducted under Project Orbis, an initiative of the FDA Oncology Center of Excellence (OCE). Project Orbis provides a framework for concurrent submission and review of oncology drugs among international partners. For this review, FDA collaborated with the Australian Therapeutic Goods Administration, Health Canada, Singapore’s Health Sciences Authority, and Switzerland’s Swissmedic. The application reviews may be ongoing at the other regulatory agencies. This review used the Assessment Aid, a voluntary submission from the applicant to facilitate the FDA’s assessment.
This application was granted priority review. The application also was granted orphan drug designation.
Healthcare professionals should report all serious adverse events suspected to be associated with the use of any medicine and device to FDA’s MedWatch Reporting System.
For assistance with single-patient INDs for investigational oncology products, healthcare professionals may contact OCE’s Project Facilitate.
