Olmutinib in T790M-positive non-small cell lung cancer after failure of first-line epidermal growth factor receptor-tyrosine kinase inhibitor therapy: A global, phase 2 study

BACKGROUND: In this open-label, international phase 2 study, the authors assessed the efficacy and safety of olmutinib in patients with locally advanced or metastatic non-small cell lung cancer (NSCLC) who had a confirmed T790M mutation and disease progression on previous epidermal growth factor receptor-tyrosine kinase inhibitor therapy.

METHODS: Patients aged ≥20 years received once-daily oral olmutinib 800 mg continuously in 21-day cycles. The primary endpoint was the objective response rate (patients who had a confirmed best overall response of a complete or partial response), assessed by central review. Secondary endpoints included the disease control rate, the duration of objective response, progression-free survival, and overall survival. Adverse events were graded according to the National Cancer Institute Common Terminology Criteria for Adverse Events (version 4.03).

RESULTS: Overall, 162 patients (median age, 63 years; women, >60%) were enrolled from 68 sites in 9 countries. At the time of database cutoff, 23.5% of enrolled patients remained on treatment. The median treatment duration was 6.5 months (range, 0.03-21.68 months). Overall, 46.3% of patients (95% CI, 38.4%-54.3%) had a confirmed objective response (all partial responses). The best overall response (the objective response rate regardless of confirmation) was 51.9% (84 patients; 95% CI, 43.9%-59.8%). The confirmed disease control rate for all patients was 86.4% (95% CI, 80.2%-91.3%). The median duration of objective response was 12.7 months (95% CI, 8.3-15.4 months). Estimated median progression-free survival was 9.4 months (95% CI, 6.9-12.3 months), and estimated median overall survival was 19.7 months (95% CI, 15.1 months to not reached). All patients experienced treatment-emergent adverse events, and 71.6% of patients had grade ≥3 treatment-emergent adverse events.

CONCLUSIONS: Olmutinib has meaningful clinical activity and a manageable safety profile in patients with T790M-positive non-small cell lung cancer who received previous epidermal growth factor receptor-tyrosine kinase inhibitor therapy.