A Phase 2 Study of Eribulin in Patients with Metastatic Angiosarcoma and 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. We report the efficacy and safety of eribulin in these vascular sarcomas in a pooled analysis of two parallel phase 2 studies.

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.

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.

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.