A Phase II Trial of Alisertib (MLN8237) in Salvage Malignant Mesothelioma

Lessons Learned: Treatment with the Aurora kinase A inhibitor yields often durable disease control, but limited tumor regression, in heavily pretreated patients with unresectable malignant pleural or peritoneal mesothelioma. In a limited sample size, MYC copy-number gain or gene amplification, a candidate predictive biomarker for alisertib, did not correlate with improved response numbers or patient outcomes. Background: Malignant mesothelioma is an aggressive disease for which few effective therapies are available. The Aurora family kinases are critical for mitotic fidelity and highly expressed in mesothelioma, wherein their inhibition leads to growth arrest in vitro. We evaluated the efficacy of alisertib, an Aurora A kinase inhibitor, in relapsed malignant mesothelioma. Methods: Twenty-six patients with previously treated, unresectable pleural or peritoneal mesothelioma were enrolled on a single-arm, single-institution phase II trial of alisertib at a dosage of 50 mg twice daily for 7 of every 21 days. The primary endpoint was 4-month disease control rate. Secondary endpoints included overall response rate, progression free survival, overall survival, safety/toxicity, and correlation of endpoints with MYC copy number. Results: Of the 25 evaluable patients treated on study, 8 (32%) experienced 4-month disease control, surpassing the futility endpoint. There were no confirmed partial or complete responses. Median progression-free and overall survival were 2.8 months and 6.3 months, respectively. No associations between MYC copy number and outcomes were observed. Conclusion: Alisertib has modest activity in this unselected malignant mesothelioma population. Several patients achieved durable disease control. Although the study did meet its prespecified futility endpoint, the sponsor elected to close the trial at the interim analysis.