A phase II trial of the histone deacetylase inhibitor belinostat (PXD101) in patients with platinum resistant epithelial ovarian tumors and micropapillary/borderline (LMP) ovarian tumors. A PMH phase II consortium trial

5518 Background: Patients with LMP ovarian tumors represent an understudied population whose tumors are intrinsically resistant to radiation and chemotherapy. Patients with platinum resistant epithelial ovarian cancer (EOC) have low response rates to conventional chemotherapy. Histone deacetylation results in loss of tumor suppressor and pro apoptotic genes in ovarian cancer cell lines. Belinostat is a pan hydroxamate, histone deacetylase inhibitor which demonstrates anti tumor activity in ovarian cancer models Methods: The aim of this phase II study is to assess the activity of belinostat in 2 patient populations: metastatic or recurrent platinum resistant (< 6 mo) EOC and LMP ovarian tumors. 3 prior lines of chemotherapy were allowed. Primary endpoints are objective response with a multinomial stopping rule, secondary endpoints include stable disease (SD) rate, survival, tolerability and assessment of molecular changes with therapy. Belinostat 1,000mg/m2/day was administered iv on days 1–5 of a 21 day c...