Phase II study of XL184 (cabozantinib) in recurrent or metastatic endometrial cancer: A trial of the PMH, Chicago, and California Phase II Consortia.

TPS5629 Background: Recurrent endometrial cancer (EC) has a poor prognosis with few therapeutic options. Targeting angiogenesis through VEGF inhibition has demonstrated real but limited efficacy. Simultaneous inhibition of angiogenesis and putative resistance mechanisms may provide more durable therapeutic responses. MET/HGF (hepatocyte growth factor) paracrine signaling has been implicated in more aggressive tumour biology, angiogenesis and resistance to VEGF targeting in EC. XL-184 (cabozantinib) is an orally bioavailable, multi-targeted inhibitor with activity against MET and VEGFR2 in addition to TIE2, RET, AXL and KIT. Methods: This phase II, multicenter single arm trial has a planned enrollment of 36 pts utilizing a Simon 2-stage design to evaluate co-primary endpoints of response rate and 12 week progression-free-survival (PFS) in pts with serous, endometrioid or mixed histology EC (experimental cohort). Eligible pts must have radiographic progression after 1 line of chemotherapy for metastatic dis...