Variations in patterns of prescribing durvalumab in stage III lung cancer: a survey of Australian Medical Oncologists

Introduction: Local Australian guidelines for the optimal management of stage III unresectable non-small cell lung cancer (NSCLC) are lacking. The American Society of Clinical Oncology (ASCO) guidelines recommend consolidation durvalumab for all patients with unresectable stage III NSCLC, irrespective of their PD-L1 expression or driver mutation status. The European Society of Medical Oncology (ESMO) differs, with consolidation durvalumab only recommended in those patients whose tumours express PD-L1. Methods: Due to differing global guidelines, we conducted an Australia and New Zealand wide survey of medical oncologists specialising in thoracic cancer to determine the variations in patterns of prescribing durvalumab in stage III unresectable NSCLC. This survey was done electronically and sponsored by the Thoracic Oncology Group of Australia (TOGA). Results: Thirty-two medical oncologists completed the survey. In patients with EGFRmutated stage III unresectable NSCLC, 6% of respondents stated that they prescribed durvalumab for all patients, while an additional 6% strongly recommended treatment. Forty-four percent suggested little benefit of consolidation durvalumab in this cohort, with an additional 19% advocating for observation only. In patients with PD-L1 negative (0%) stage III unresectable NSCLC, 13% of respondents prescribed durvalumab for all patients, while an additional 56% strongly recommended treatment. Interestingly, 18%, 10%, and 10% of prescribers discussed self-funded oral tyrosine kinase inhibitor therapy in patients with EGFR, ALK, or ROS-1-mutated NSCLC respectively as a substitute for consolidation durvalumab. Conclusion: Overall, the clinical practice of Australian and New Zealand Medical Oncologists is variable, but remains consistent with either the ASCO or ESMO guidelines. Local practice guidelines are required to ensure consistency in prescribing patterns across Australia, as well as providing evidence for selffunded treatments outside standard of care.