Single-Agent Pemetrexed for Chemonaïve and Pretreated Patients with Malignant Pleural Mesothelioma: Results of an International Expanded Access Program

IntroductionPemetrexed has established efficacy, and is the backbone for chemotherapy in patients with malignant pleural mesothelioma (MPM). An International Expanded Access Program provided >3000 mesothelioma patients with access to single-agent pemetrexed or pemetrexed plus platinum analogs (cisplatin or carboplatin) in 13 countries. In this article, we report the safety and efficacy data of MPM patients who were treated with single-agent pemetrexed (n = 812).MethodsPatients with histologically confirmed MPM, not amenable to curative surgery, received pemetrexed (500 mg/m2) once (day 1) every 21 days with standard premedication and vitamin supplementation. Investigator-determined response and survival data were recorded at the end of study participation. Myelosuppression data were also collected.ResultsAll 812 MPM patients (319 chemonaïve; 493 pretreated) received single-agent pemetrexed (≥1 dose) and were evaluated for safety. A total of 643 patients (247 chemonaïve, 396 pretreated) were evaluated for efficacy. Of the chemonaïve patients evaluated for efficacy (n = 247), the overall response rate was 10.5%, median time to progressive disease (TTPD) was 6.0 months, and median survival was 14.1 month. Of the pretreated patients evaluated for efficacy (n = 396), the overall response rate was 12.1%, median TTPD was 4.9 months, and the median survival was not estimable due to high censoring. Common terminology criteria grade 3/4 hematologic toxicity was mild in both groups, with neutropenia (<18%) as the main toxicity.ConclusionsIn the present expanded access program, single-agent pemetrexed demonstrated promising activity in MPM in both chemonaïve and pretreated patients, with TTPD of 6.0 and 4.9 months, respectively, 1-year survival ≥54.7%, and mild hematologic toxicity.