Efficacy and safety of pemetrexed in elderly cancer patients: Results of an integrated analysis

Purpose: To analyze pemetrexed in elderly patients (>= 65 years) based on data collected in three randomized, phase III registration trials. Methods: Patients who received pemetrexed as monotherapy or in combination with another drug were included in this analysis (N=764). In all studies, pemetrexed 500 mg/m(2) was administered every 21 days. Data from patients receiving pemetrexed were stratified by age 65 years. Results: Out of the 764 patients randomized, 271 were >= 65 years of age (35.4%). Of these, 28% had non-small cell lung cancer, 41% pancreatic cancer, and 31% had malignant pleural mesothelioma that was either locally advanced or metastatic. The overall response rate of the integrated database of elderly patients was 21.4%, with complete response in three patients (1.11% in >= 65 years vs. 1.01% in <65 years), partial response in 55 (20.30% vs. 19.68%), and stable disease in 116 (42.80% vs. 43.00%). Median survival time was 8.34 months in both groups, and median time to progressive disease was 4.80 months versus 4.60. Toxicity observed in the elderly group included 70 patients (25.8% vs. 17.0%; p=0.005) with grade 4 toxicity; myelosuppression was the major toxicity, with grade 3/4 neutropenia in 33% versus 22% (p < 0.05), and thrombocytopenia in 13% versus 6% (p < 0.05). Febrile neutropenia occurred in 4.8% versus 4.7% of patients. Non-hematological grade 3/4 events were fatigue (10.3% vs. 9.5%) and nausea (6.3% vs. 6.5%). Conclusions: Pemetrexed produced similar treatment effects in older and younger patients, and appeared to be well tolerated in the elderly population. This analysis was limited by the pooling of different disease types and the lack of uniform treatment regimens. (C) 2008 Elsevier Ireland Ltd. All rights reserved.