513 Background: The anti-tumor and anti-edema effects of BEV provide a rationale for testing in BCBM. Carboplatin (C) is associated with CNS responses across multiple tumor types. We evaluated BEV + C in pts with BCBM. Methods: Pts with progressive, measurable BCBM (>/= 1 cm in longest dimension) were eligible. Cycle 1: BEV 15 mg/kg on Day 1, followed on Day 8 by carboplatin AUC=5 (plus trastuzumab if HER2+). In subsequent cycles, pts received BEV + C on Day 1 (plus trastuzumab if HER2+) of a 3 week (wk) cycle. Standard brain MRI was obtained at baseline (BL) and every 2 cycles. Non-CNS scans (CT or MRI) were performed after 2 cycles, 4 cycles, then every 4 cycles. Correlative brain imaging was obtained at BL, 12-96 hours after the first dose of BEV, and after 2 cycles. Circulating tumor cells and blood for VEGF polymorphisms were also collected. The primary endpoint was composite CNS objective response rate (CNS ORR). CNS partial response required all of the following: >/= 50% reduction in volumetric sum of target CNS lesions compared to BL, no progression of non-target lesions, no new lesions, stable/decreasing steroid dose, no progressive neurologic signs or symptoms, and no progression of non-CNS disease by RECIST 1.0. The study used a 2-stage design to distinguish between ORR 5% vs 20% (responses in >/= 1/12 pts to enter 2ndstage; responses in >/= 4/37 pts needed to be promising). Results: 38 pts were enrolled between 11/3/09-8/24/12 (30 HER2+; 8 HER2-negative). Most (76%) pts had received >/=2 lines of metastatic chemotherapy. 97% of pts with HER2+ disease received prior trastuzumab; 73% had prior lapatinib. All but 5 pts progressed after WBRT and/or SRS. As of 1/15/13, 3 pts remain on protocol therapy; 22 patients have died. The composite CNS ORR was 63% (95% CI 46%-78%). CNS ORR by RECIST was 45%. CNS responses were observed in both HER2+ and HER2-negative pts. Of 34 pts with >/= 24 wks potential follow-up time, median number of cycles was 8 (range 1-19). One grade 2 CNS hemorrhage event was reported; there were no cases of grade 3/4 CNS hemorrhage. Conclusions: BEV + carboplatin is associated with a high rate of durable CNS response in pts with BCBM. Updated results, including progression-free and overall survival will be presented. Clinical trial information: NCT01004172.
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