This was a multicenter, open-label Phase 1 study of DS-1205c in combination with gefitinib in subjects with metastatic or unresectable EGFR-mutant NSCLC...25% of patients had stable disease (n = 5) and 70% (n = 14) experienced disease progression as the best overall response. The disease control rate was 25% (95% CI: 8.7–49.1).