A Phase 2 Study of Eribulin in Patients with Metastatic Angiosarcoma and Epithelioid Hemangioendothelioma

PURPOSE: 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. We report the efficacy and safety of eribulin in these vascular sarcomas in a pooled analysis of two parallel phase 2 studies. PATIENTS AND METHODS: Patients more than age 18 years with metastatic or recurrent angiosarcoma or EHE were treated with eribulin (1.4 mg/m2 on days 1 and 8 of a 21-day cycle) until progression or unacceptable toxicity. The primary endpoint was objective response rate (ORR) by RECIST 1.1. RESULTS: Twenty-nine patients were accrued to the study, with 25 (85%) having had prior taxane exposure. We observed an ORR of 17% for angiosarcomas, with 6 of 23 (26%) patients achieving disease stability for greater than 6 months, and an ORR of 33% (2/6) for EHE, with two of six continuing treatment for over 12 months. Five patients experienced a >1.3-fold time to progression ratio (TTP2/TTP1) on eribulin compared with the immediately prior therapy. Eribulin tolerability was consistent with published data. CONCLUSIONS: Eribulin showed clinical activity in this largely taxane-pretreated population. Future studies will be needed to confirm activity. See related commentary by Chen, p. 2130.