Poster Presentation Clinical Oncology Society of Australia Annual Scientific Meeting 2024

The use of durvalumab following definitive chemo-radiotherapy in unresectable stage III non-small-cell lung cancer – an experience of the Northern Adelaide Cancer Centre (#256)

Rama Devi Penumarty 1 , Michelle Forgione 1 , Dainik Patel 1 , Christopher Hocking 1 , Rohit Joshi 1 , Vineet Kwatra 1
  1. Medical Oncology, Northern Adelaide Local Health Network, Elizabeth Vale, South Australia, Australia

Background

The PACIFIC trial demonstrated a significant improvement in progression free survival (PFS) and overall survival (OS) with the addition of maintenance durvalumab following definitive chemo-radiotherapy (CRT) in patients with unresectable stage III non-small-cell lung cancer (NSCLC). Durvalumab maintenance following CRT became standard-of-care following in Australia in March 2021.

 

Objectives

The primary objective was to audit the rate of durvalumab uptake among patients who received definitive CRT for Stage III unresectable NSCLC at the Northern Adelaide Cancer Centre. Secondary objectives were to compare PFS and OS between patients who received durvalumab and patients who did not receive durvalumab, and to establish the reasons for patients not receiving durvalumab.

 

Methods

This retrospective data was collected from patients who underwent definitive concurrent CRT for stage III unresectable NSCLC between 2021 and 2023 (n=24). Patients with actionable EGFR, ALK or ROS mutations were excluded. Statistical analyses were performed using SPSS Software. Data cut-off date was 1st of June 2024. Median follow-up time was 33.9 months.

 

Results

Of the 24 patients included in the final analysis, 10 received durvalumab maintenance therapy (41.7%), of which five completed the planned 12-month course. The most common reason for early discontinuation was disease progression (n=3). Fourteen patients (58.3%) did not receive durvalumab. Common documented reasons for not receiving durvalumab included medical history or CRT-related toxicity (n=4) and disease progression (n=3). There was a numerical difference but not statistically significant difference between patients who received or did not receive durvalumab for median PFS (14.7 vs 7.4 months, HR=0.730, 95% CI=0.219–2.435) and median OS (35.9 months vs not reached, HR=0.616, 95% CI=0.149–2.539).

 

Conclusion                                                  

This audit identified a lower-than-expected uptake of maintenance durvalumab among patients with unresectable stage III NSCLC treated with concurrent CRT. However, approximately half the patients who were prescribed durvalumab completed the 12-month course, consistent with PACIFIC study.