The phase Ⅲ randomised BR.21 study demonstrated that in patients with relapsed advanced NSCLC, erlotinib (Tarceva) improved survival and prolonged time to symptom deterioration compared with placebo (Shepherd et al.NEJM 2005 ;353:123 32).Erlotinib was well tolerated, with rash and diarrhoea the most common adverse events (AEs) , both being generally mild to moderate in severity.The TRUST study was designed to allow access to erlo tinib for eligible patients in countries where the drug had not yet received a licence.More than 7,040 patients have been enrolled into this open-label, non-randomised study at 552 centres in 52 countries worldwide.Methods : Eligi ble patients with stage ⅢB/Ⅳ NSCLC had failed previous chemotherapy for advanced disease (≤ 2 prior regi mens) or were unsuitable for chemotherapy.Erlotinib was administered orally 150mg/day until disease progression or unacceptable toxicity.366 patients in China were included in the analysis at the data cut-off (06/06/07).Dis ease Control Rate is 81% (PR 23% ,SD 58%).86% of them experienced rash, only 4% of them with grade >2 rash.Incidence of Tarceva-related SAE is 2%.