A randomized phase III trial of active symptom control (ASC) with or without chemotherapy in the treatment of patients with malignant pleural mesothelioma: First results of the Medical Research Council (MRC) / British Thoracic Society (BTS) MS01 trial

Abstract

LBA7525 Background: Although chemotherapy is widely used in the treatment of mesothelioma it has never been compared in a randomized trial with ASC alone. Two chemotherapy regimens that had shown good symptom palliation in phase II studies were chosen for investigation. Methods: Patients with malignant pleural mesothelioma were randomized to ASC alone (regular follow-up in a specialist clinic, and treatment could include steroids, analgesics, bronchodilators, palliative radiotherapy, etc), ASC+MVP (4 × 3-weekly cycles of mitomycin 6g/m2, vinblastine 6mg/m2, and cisplatin 50mg/m2), or ASC+N (12 weekly injections of vinorelbine 30mg/m2). 420 patients were required to detect a 3-month improvement in median survival with ASC+CT (both chemotherapy arms combined). Quality of Life (QL) was assessed using the EORTC QLQ-C30. Results: 409 patients were accrued (136 ASC, 137 ASC+MVP, 136 ASC+N). Median age: 65 years, male: 91%, Performance status 0: 23%, Epithelial histology: 73%, Stage III: 33%, Stage IV: 48%. In the ASC+MVP group 61% received all 4 cycles, and in the ASC+N group 49% received at least 10 weekly cycles. Good symptom palliation (defined as prevention, control or improvement) was achieved in all 3 groups, and no between-group differences were observed in 4 pre-defined QL subscales (physical functioning, dyspnoea, pain and global QL). A small (not conventionally significant) survival benefit was seen for ASC+CT (349 deaths, HR 0.89, 95%CI 0.72, 1.12, p=0.32). Median survival: ASC: 7.6 months, ASC+CT: 8.5 months. Exploratory analyses suggested a survival advantage for vinorelbine compared to ASC alone (HR 0.81, 95%CI 0.63, 1.05, p=0.11), with a median survival of 9.4 months, but no evidence of a benefit with MVP (HR 0.98, 95%CI 0.76, 1.28), p=0.91). Conclusions: This is the 2nd largest ever randomized trial in mesothelioma and the first to compare ASC with or without chemotherapy. Although the addition of chemotherapy to ASC did not result in a conventionally significant survival benefit, there was an indication that vinorelbine should be investigated further, and that MVP probably has no role in this disease. [Table: see text]