Multinational phase 2 trial of erubulin for metastatic angiosarcoma or epithelioid hemangioendothelioma

Angiosarcoma and epithelioid hemangioendothelioma (EHE) are two rare vascular sarcomas with limited therapeutic options. Prior reports have shown sensitivity to microtubule-targeting agents in these histologies. Pooled analysis of two parallel phase 2 studies in Australia and the USA investigated efficacy and safety of eribulin in these sarcomas. The analysis included patients over age 18 years with metastatic or recurrent angiosarcoma or EHE. Patients received eribulin 1.4 mg/m² on days 1 and 8 of 21-day cycles until progression or unacceptable toxicity. The primary endpoint was objective response rate. Among 29 included patients, 25 (85%) had prior taxane exposure. The ORR was 17% for angiosarcomas, with 26% achieving disease stabiltiy for greater than 6 months. The ORR for EHE was 33%, with 2 of 6 patients continuing treatment for over 12 months. Five patients (17%) experienced a > 1.3-fold time to progression ratio (TTP2/TTP1) on eribulin compared to immediate prior therapy. Eribulin tolerability was consistent with published data. The authors conclude that eribulin showed clinical activity in this largely taxane-pretreated population.