Clinical Factors Associated With Non‐Completion of Durvalumab Maintenance Therapy After Chemoradiotherapy in Patients With Locally Advanced Non‐Small Cell Lung Cancer: A Single‐Center Retrospective Study
Masaaki Kotake, Satoshi Watanabe, Yuki Sakai, Toshiaki Kikuchi, Akira ToyamaABSTRACT
Background
Durvalumab maintenance following concurrent chemoradiotherapy (CCRT) is the standard treatment for unresectable stage III non‐small cell lung cancer (NSCLC); however, some patients discontinue treatment before completing 12 months. We explored whether pretreatment peripheral blood inflammatory and nutritional markers are associated with durvalumab non‐completion.
Methods
We retrospectively reviewed patients with locally advanced NSCLC who initiated durvalumab between August 2018 and April 2024. Laboratory data obtained within 7 days before the first dose were analyzed. Completion was defined as 12 months (365 days) of treatment. Routine laboratory parameters and inflammatory/nutritional indices were compared between completers and non‐completers. Exploratory multivariable logistic regression and clinically adjusted sensitivity analyses were performed.
Results
Eighty patients were included: 36 completers and 44 non‐completers. Durvalumab was discontinued because of disease progression ( n = 24), radiation pneumonitis ( n = 14), immune‐related adverse events ( n = 5), and aspiration pneumonia ( n = 1). Conventional inflammatory indices did not differ between groups. In the primary exploratory multivariable model, a higher albumin‐to‐globulin (A/G) ratio was associated with durvalumab completion (OR, 9.74; 95% CI, 1.01–93.9; p = 0.048), whereas RDW‐SD showed a non‐significant inverse association with completion (OR, 0.942; 95% CI, 0.883–1.01; p = 0.076). After adjustment for age, ECOG performance status, and histology, these associations were not statistically significant.
Conclusions
Lower A/G ratio and higher RDW‐SD before durvalumab initiation may be associated with non‐completion. Given the exploratory design, limited sample size, attenuation after clinical adjustment, and heterogeneous reasons for discontinuation, these findings require external validation.