Sequential administration of sunitinib (SU) and docetaxel (D) in women with advanced breast cancer (ABC): an exploratory evaluation

14534 Background: SU is an oral broadly multitargeted tyrosine kinase inhibitor with major inhibitory activity on VEGFRs, PDGFRs, KIT, FLT3 and RET. This multitargeted approach may be beneficial in heterogeneous diseases such as BC. SU has shown single- agent activity in patients (pts) with heavily pretreated metastatic (M) BC (objective response rate 11%) and its antitumor activity is enhanced by D in mouse BC xenografts. In a phase I study, MTDs in solid tumor pts were SU 37.5 mg/d on Schedule 2/1 and D 75 mg/m2. Here we report on an exploratory study of SU+D given at their MTDs as first-line treatment to ABC pts. Methods: Pts with unresectable, locally recurrent or MBC who relapsed after anthracycline-based adjuvant chemotherapy received IV D at 75 mg/m2 q3w on day 1 and oral SU at 37.5 mg/d for 2 wks starting on day 2 of a 3-wk cycle (Schedule 2/1). The target number of pts was 20. The primary objective was the PK profile of SU+D. Secondary endpoints were safety and preliminary activity. After discont...