Utilization of extended-interval, fixed-dosing of durvalumab, every 4 weeks, in U.S. patients with unresectable stage III NSCLC following concurrent chemoradiation.

[BACKGROUND] Durvalumab was initially approved for stage III unresectable non-small cell lung cancer (NSCLC) post-concurrent chemoradiation at 10 mg/kg every two weeks, and starting in November 2020, at 1500 mg every four weeks (Q4W). Real-world evidence is limited on durvalumab Q4W dosing utilization and discontinuation, especially in community-based oncology settings.

[METHODS] In this retrospective cohort, we examined patients with stage III unresectable NSCLC who initiated durvalumab between 3 January 2019 and 12/31/2021, including those who switched to Q4W dosing or received Q4W dosing only, with follow-up until durvalumab discontinuation, health plan disenrollment, death, or study's end.

[RESULTS] Of the 102 patients (mean age: 71 years; 46.1% female; 46.1% non-White; 80.4% formerly smoked), 40 switched to Q4W dosing, and 62 received Q4W dosing only. Median duration of treatment (DoT) was 10.0 months overall and 7.5 months for Q4W only. About one-third of patients receiving Q4W dosing completed treatment. Discontinuation occurred in 51.5% of all patients and 65.5% receiving Q4W dosing only. The most common discontinuation reasons were disease progression (17.7%) and pneumonitis (14.7%).

[CONCLUSION] In this diverse community-based cohort, Q4W dosing outcomes, including DoT and completion rate, were comparable to other real-world studies with Q2W dosing and the PACIFIC and PACIFIC-R trials.