Clinical efficacy of dacomitinib in rechallenge setting for patients with epidermal growth factor receptor mutant non–small cell lung cancer: A multicenter retrospective analysis (TOPGAN2020-02)

Background: Dacomitinib is the second-generation epidermal growth factor receptor (EGFR)-tyrosine kinase inhibitor (TKI) for mutant non–small cell lung cancer (NSCLC). EGFR-TKIs are often re-administered in Japan after the disease progression prior EGFR-TKI. There is little evidence of dacomitinib in rechallenge setting. This study evaluated clinical outcomes of dacomitinib in rechallenge setting. Methods: Patients who received dacomitinib for advanced EGFR-mutant NSCLC who had progressed after EGFR-TKI in nine institutions in Japan were included in the analyses. Results: In total, 43 patients were analyzed. The median progression-free survival (PFS) was 4.3 months (95% confidence interval [CI], 2.5–5.6). The overall survival (OS) was 10.5 months (95% CI, 7.4–not reached). The overall response rate was 25.5% (95% CI, 13.1–33.7). Subset analysis indicated that patients with EGFR exon 21 L858R showed longer PFS than those with EGFR exon 19 deletion (5.8 vs. 4.1 months) (p = 0.018). The most common adverse events leading to dose modification were diarrhea, paronychia, rash, and oral mucositis. Conclusion: In the real practice in Japan, dacomitinib showed a worthwhile treatment option for NSCLC patients with EGFR mutation after failure of previous EGFR-TKI. The benefit was especially pronounced in patients with the exon 21 mutation.