Background: Anti-angiogenic therapy with the monoclonal anti-VEGF antibody Bevacizumab (Bev) in combination with chemotherapy increases overall response rates (ORR) and progression free survival (PFS) but without impact on overall survival. SOR, an anti-angiogenic multi-tyrosine kinase inhibitor (TKI) also targeting tumor growth directly, is approved for advanced renal cell and hepatocellular carcinoma. Three phase IIb trials (SOLTI-0701, NU07B1, AC01B07) have reported efficacy of SOR in combination with chemotherapy in MBC, even after prior Bev (AC01B07). As TKIs might have superior activity we conducted this trial in first-line MBC. Methods: Pts were randomized to DOC (75mg/m² q3w) + either SOR (400 p.o. twice daily (BID)) or placebo. Following an amendment after the inclusion of 63 pts, the SOR starting dose was reduced to 400 mg/d for cycle 1 and 600 mg/d for cycle 2 with the option to increase the dose to 800 mg/d after the second cycle in the absence of > grade 1 toxicities. The planned sample size was 288, but due to slow accrual the study was closed early after 102 patients. The primary end point was progression free survival (PFS). Important secondary endpoints were overall response rate (ORR), duration of response, time to progression (TTP), overall survival (OS) and safety/tolerability. Here we report the data after 78 PFS events in 95 evaluable patients. Results: Median age was 57 years with 71.6% of patients being post-menopausal. 74.5 of patients had a positive estrogen receptor (ER) status and 47.1% and 48.0% of patients had a tumor grading 2 and 3, respectively. Overall, as of December 13^th2013, the median PFS was 7.4 months with a median TTP of 7.9 months, a median duration of response of 8.9 months and an ORR of 47.1%. The corresponding median OS was 21.2 months. Grade 3 to 4 toxicities (> 5% of pts) included neutropenia (31%), lymphopenia (25%), leukopenia (25%), HFSR (19%), diarrhea (11%), febrile neutropenia (9%), and fatigue (8%). Conclusions: Final efficacy data including overall survival and detailed safety data will be presented by treatment arm. Comparative efficacy and safety data will also be presented by SOR dosing schedule. Clinical trial information: EUDRACT-Nr. 2008-001090-15.