Phase II study of erlotinib in elderly patients with non-small cell lung cancer harboring epidermal growth factor receptor mutations

Epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors are key drugs in the treatment of non-small cell lung cancer (NSCLC) harboring EGFR activating mutations. We assessed the efficacy and safety of one EGFR tyrosine kinase inhibitor, erlotinib, in elderly Japanese patients with EGFR-mutated NSCLC. Elderly patients aged 75 or older with advanced or recurrent NSCLC and EGFR mutations (exon 19 deletion or L858R mutation in exon 21) were enrolled in this prospective phase II trial. Patients received 150 mg erlotinib per day orally. The primary end point was the overall response rate. Between March 2013 and November 2014, 32 patients were enrolled with median age 80 years. All tumors had adenocarcinoma histology, and 20 patients (62.5 %) had an L858R mutation. The response rate was 56.3 % [95 % confidence interval (CI) 39.4-72.0 %], and the disease control rate was 90.6 % (95 % CI 75.2-97.6 %). Median progression-free survival was 15.5 months (95 % CI 11.2-not reached). Skin disorder was the most common adverse event, and grade 4 drug-related interstitial lung disease occurred in one patient. Erlotinib is effective and tolerated in elderly patients with EGFR mutation-positive NSCLC.