UK Real-World Evidence of Using Durvalumab Plus Cisplatin and Gemcitabine in Advanced Biliary Tract Cancer via an Early Access Scheme

Abstract

Background: Durvalumab (anti-PD-L1) in combination with gemcitabine and cisplatin has become the first-line treatment for patients with locally advanced, surgically unresectable, or metastatic biliary tract cancer, following the survival benefit demonstrated in the TOPAZ-1 phase III trial. This study presents real-world data from UK centres in patients who received early access to the regimen via AstraZeneca's scheme. The aim was to assess the safety and efficacy of this treatment approach in routine clinical practice and compare it to outcomes reported in the TOPAZ-1 trial. Method: This retrospective study included patients with locally advanced, surgically unresectable, or metastatic biliary tract adenocarcinoma who received durvalumab in combination with gemcitabine and cisplatin. Data were collected across ten UK centres. The primary endpoint was progression-free survival (PFS), with secondary endpoints including overall survival (OS), overall response rate (ORR), and safety outcomes, encompassing both chemotherapy and immunotherapy-related adverse events (AEs). Results: A total of 134 patients treated between April 2022 and December 2023 were included. The median follow-up was 12.8 months (95% CI: 11-16.8). The median PFS was 8.83 months (95% CI: 5.73-11.7), closely aligning with the 7.2 months reported in TOPAZ-1 (95% CI: 6.7-7.4). The median OS was 12 months (95% CI: 10.7-13.9), slightly below the 12.8 months observed in TOPAZ-1 (95% CI: 11.1-14.0). The ORR was 29.1% (TOPAZ-1: 26.7%), and the disease control rate was 61.2%. In terms of safety, 64 patients (52.3%) experienced any-grade AEs, and 9 patients (6.8%) had grade 3-4 AEs, representing a lower toxicity profile than TOPAZ-1. Immunotherapy-related AEs occurred in 25 patients (18.7%), with grade 3-4 events in 3%. Conclusions: These real-world findings from UK cancer centres support the outcomes of the TOPAZ-1 trial, demonstrating comparable efficacy and a favourable safety profile for durvalumab combined with gemcitabine-cisplatin as first-line treatment for advanced biliary tract cancer.

Keywords: biliary tract cancer; cholangiocarcinoma; durvalumab; immune checkpoint inhibitors; immunotherapy; real world evidence.

Figure 2

Kapla–Meier curves for OS, stratified by disease site.

Figure 1

Kaplan–Meier curves for OS and PFS.

Figure 3

Waffle chart illustrating the response to treatment.

Figure 4

Box plots of patients who received maintenance durvalumab. (a) Box plot showing the number of maintenance cycles of durvalumab given to patients stratified by disease site. (b) Box plot showing the distribution of the number of cycles of maintenance durvalumab across all disease sites with individual data points.