Association Between PD-L1 Score and the Outcomes of Consolidation Durvalumab in a Large Nationwide Series of Patients With Stage III NSCLC Treated With Chemoradiotherapy

Background

The Pacific trial reported improved outcomes when durvalumab was administered following concurrent chemoradiotherapy (CRT) for stage III NSCLC. Post-hoc subgroup analysis did not show favorable results for PD-L1 negative cases. We compared nationwide survival data with the trial outcomes, and evaluated the influence of PD-L1.

Patients and methods

Data from the Netherlands Cancer Registry were queried regarding patients with clinical stage III who underwent CRT, either by concurrent or sequential administration. Predictors for the use of consolidation treatment with durvalumab were evaluated by tabulations and logistic regression analysis. Overall survival (OS) was calculated from start of radiation or start of durvalumab and was stratified by PD-L1 score.

Results

Between 2017 and 2021, application of consolidation durvalumab increased from 2% to 21%, 40%, 57%, 62%, respectively. In the period 2020-2021, durvalumab use was more frequent among patients with younger age, concurrent CRT, better performance score and proton radiation, but was irrespective of PD-L1 score.

For patients receiving durvalumab (n = 1639), the 4-year OS was 53% overall (95%CI 50-57), and it was 56% (95%CI 52-60) after concurrent CRT. Four-year OS was considerably better for the PD-L1 subgroup ≧50% at 67% (95%CI 59-73), and it was similar for PD-L1 subgroups 0 and 1-49, at 51% (95%CI 42-58) and 46% (95%CI 39-54), respectively.

Conclusion

In real-world clinical practice, survival outcomes were equivalent to results from trial series. Overall survival in patients with negative PD-L1 was similar to the survival in patients with PD-L1 1-49, questioning the restrictions imposed by the European Medicines Agency.