Safety of erlotinib treatment in outpatients with previously treated non-small-cell lung cancer in Japan

Purpose Erlotinib is the first epidermal growth factor receptor-tyrosine kinase inhibitor shown to provide a survival benefit for advanced non-small-cell lung cancer (NSCLC) patients. Adverse drug reactions of erlotinib in Japanese, which may be very different from those in Caucasians because of differences in genetic background, have not been fully reported. Therefore, we aimed to clarify the safety profile of erlotinib. Methods Forty-eight patients with pretreated NSCLC were treated with erlotinib between March 2008 and January 2009 in this historical cohort study at Kyoto University Hospital Outpatients Oncology Unit. Erlotinib 150 mg/day was administered until progressive disease or discontinuation due to adverse events. The primary endpoint was frequency and degree of adverse events, and secondary endpoints were clinical efficacy including response rate, disease control rate, progression-free survival and overall survival. Results Of 48 patients, 3 patients experienced erlotinib-induced interstitial pneumonitis, which appeared on day 15 and 70 in 2 patients who recovered and on day 8 in 1 patient who died. The incidences of pruritus, dry skin, diarrhea and stomatitis rapidly increased within 14 days after the start of medication with erlotinib. However, these adverse events were well controllable in outpatients treated with erlotinib. Overall response rate was 10% and disease control rate was 68%. The median progression-free survival was 58 days (95% confidence interval 30-118) and the median overall survival was 229 days (95% confidence interval 135-not available). Conclusions Outpatients with NSCLC can be treated with initial administration of erlotinib by careful management.