580P - Efficacy and safety of dacomitinib as first-line treatment for advanced non-small cell lung cancer (NSCLC) patients with epidermal growth factor receptor <italic>(EGFR)</italic> 21L858R mutation: A multicenter, ambispective, consecutive case-series study

Background

ARCHER 1050 has demonstrated a potential efficacy of first-line dacomitinib for Chinese non-small cell lung cancer (NSCLC) patients with epidermal growth factor receptor (EGFR) 21L858R mutation but with limited data. This study aims to provide more evidence for the application of first-line dacomitinib treating advanced NSCLC patients with EGFR 21L858R mutation in China and explore influential factors of clinical outcomes.

Methods

A longitudinal, consecutive case-series, multi-center study with mixed prospective and retrospective data was conducted. The primary endpoint was progression-free survival (PFS), and the secondary endpoints included duration of treatment (DOT), overall survival (OS), objective response rate (ORR), disease control rate (DCR) and safety.

Results

A total of 155 EGFR 21L858R mutant patients treated with first-line dacomitinib were included into this study. The median follow-up time for these patients was 20.4 months. Among 134 patients with target lesions, the ORR was 70.9% and the DCR was 96.3%. The median PFS was 16.3 months (95%CI, 13.7-18.9). Univariate Cox regression analysis suggested that baseline brain metastasis (BM) status (with vs. without BM: HR, 1.171; 95%CI, 0.730-1.878; p = 0.513) and initial dose (45mg vs. 30mg: HR, 0.980; 95%CI, 0.564-1.701; p = 0.943) didn’t have significant impact on the median PFS. The median DOT was 21.0 months (95%CI, 17.5-24.6) and the median OS was not reached. The most common grade 3-4 adverse events were rash (10.4%), diarrhea (9.1%), stomatitis (7.1%) and paronychia (4.5%).

Conclusions

First-line dacomitinib treatment demonstrated promising efficacy and tolerable adverse events among Chinese NSCLC patients with EGFR 21L858R mutation.

Clinical trial identification

Editorial acknowledgement

Legal entity responsible for the study

The authors.

Funding

Has not received any funding.

Disclosure

All authors have declared no conflicts of interest.