Pemetrexed With or Without Carboplatin for Elderly Non-squamous Non-small Cell Lung Cancer

The treatment of NSCLC in elderly has been subject to discussion for years. While platinum doublets consisting of cisplatin or carboplatin and another cytotoxic agent demonstrate a survival advantage compared with single agents generally, evidence of treatment efficacy for patients with diminished performance status (PS) or with age older than 70 years is limited. Guidelines from the US and Europe have preferred single-agent chemotherapy for the elderly and PS 2 patients. However, increasing studies are exploring this issue and presenting data that favour doublet therapy. The addition of carboplatin to paclitaxel and cisplatin to docetaxel have shown evidence that patients over 70 benefit more in face of increased toxicities. This study is designed to be multi-center, open-label, prospective, randomized, two-arm, parallel, phase III trial of elderly patients(≥70 years old) with metastatic non-squamous NSCLC (Stage IV by AJCC 7th) who have not received prior systemic chemotherapy or biological therapy. Approximately 266 patients will be enrolled into the trial. This study compares the doublet therapy of pemetrexed (500 mg/m2) and carboplatin (AUC 5 mg/mL\*min) administered intravenously every 21 days for 4 cycles followed by pemetrexed (500 mg/m2) every 21 days for maintenance therapy (Arm A) to single therapy of pemetrexed (500 mg/m2) every 21 days till progression or unacceptable toxicity (Arm B). Pemetrexed will be administered with vitamin B12 and folate supplements.