Single-agent maintenance therapy for advanced-stage non-small cell lung cancer: A meta-analysis.

Abstract

7553 Background: Maintenance therapy is a new treatment paradigm following first-line combination chemotherapy for patients with advanced non-small cell lung cancer (NSCLC). We conducted a meta-analysis of randomized studies that evaluated single agent maintenance therapy. Methods: We conducted an electronic literature search of public databases (MEDLINE, EMBASE, Cochrane library) and manual search of conference proceedings of ASCO and World Conference on Lung Cancer using relevant terms. Eligible studies were identified and reviewed independently by two co-authors. Randomized trials that reported the effect of single agent maintenance therapy on survival in NSCLC patients were included. A formal meta-analysis was conducted using Comprehensive Meta Analysis software (Version 2.0). The outcome data were pooled and reported as hazard ratio (HR). The primary outcome of interest was overall survival (OS) and secondary outcome was progression free survival (PFS). Results: We reviewed 210 published reports. Ten were eligible for inclusion (3 meeting abstracts, 7 journal publications) with a total of 3451 patients (maintenance arm/control arm- 1942/1509, median age 62.5 years, male -72 %). The OS (HR 0.87, 95% CI 0.82 to 0.94, P=0.0003) and PFS (HR 0.84, 95% CI 0.80 to 0.88, P< 0.0001) were superior with maintenance therapy. ‘Switch’ maintenance therapy was associated with significant OS and PFS improvement (HR 0.86 CI 0.80 to 0.93, P= 0.00046; PFS HR 0.71 CI 0.66 to 0.77, P<0.0001). Despite a modest improvement in PFS (HR 0.92, CI 0.87 to 0.98, P= 0.007), “continuation” maintenance therapy was not associated with survival benefit (HR 0.92, CI 0.77 to 1.08, P=0.33). Improvements in OS and PFS were observed with EGFR-targeted agents (HR 0.86, CI 0.78 to 0.95, P= 0.006; HR 0.76 CI 0.70 to 0.83, P<0.0001) and cytotoxic agents (HR 0.88, CI 0.80 to 0.97, P=0.018; HR 0.87, CI 0.82 to 0.91, P<0.0001). Conclusions: Single agent maintenance therapy improves overall survival, though statistical significance was only noted with ‘switch’ maintenance. Survival benefit was observed for chemotherapy and EGFR-targeted therapy. Supported by NIH P01 CA116676. TKO, FRK and SSR are Distinguished Cancer Scholars of the Georgia Cancer Coalition.