Inclusion Criteria:

- Histologically or cytologically confirmed adenocarcinoma of the breast.

- Measurable or evaluable locally advanced or metastatic disease.

- Age ≥18 years.

- Disease progression during or after treatment with a bevacizumab-containing regimen
in the adjuvant or first-line metastatic setting.

- Patients must have discontinued chemotherapy at least 3 weeks prior to randomization.

- No more than one prior chemotherapy regimen for locally advanced or metastatic
disease.

- Prior hormonal therapy allowed provided it has been discontinued prior to
randomization.

- Prior radiation therapy is allowed but must be completed at least 3 weeks prior to
randomization. Previously radiated area(s) must not be the only site of disease.

- ECOG Performance Status of 0 or 1.

- Adequate bone marrow, liver, and renal function

- Women of childbearing potential must have a negative serum pregnancy test performed
within 7 days prior to randomization, and must agree to use adequate contraception
prior to study entry, for the duration of study participation and 28 days after the
last study drug dosing.

- Patients must be able and willing to sign a written informed consent.

- Patients must be able to swallow and retain oral medication.

Exclusion Criteria:

- Patients with breast cancer over-expressing human epidermal growth factor receptor 2
(HER-2) (gene amplification by FISH or 3+ over-expression by immunohistochemistry).
Patients with unknown HER-2 status are not eligible.

- Patients with active brain metastases.

- Major surgery, open biopsy, or significant traumatic injury within 4 weeks of
randomization.

- Prior use of gemcitabine/capecitabine or sorafenib.

- Evidence or history of bleeding diathesis or coagulopathy.

- Serious, non-healing wound, ulcer, or bone fracture.

- Substance abuse, or medical, psychological, or social condition that may interfere
with the patient's participation in the study or evaluation of the study results.

- Use of cytochrome P450 enzyme-inducing anti-epileptic drugs is not allowed.

- Clinically significant cardiac disease

- Uncontrolled hypertension

- Thrombolic, embolic, venous, or arterial events such as a cerebrovascular accident
including transient ischemic attacks within the past 6 months.

- Pulmonary hemorrhage/bleeding event > NCI-CTCAE Grade 2 within 4 weeks of
randomization.

- Any other hemorrhage/bleeding event ≥ NCI-CTCAE Grade 3 within 4 weeks of
randomization.

- Active clinically serious infection > NCI-CTCAE Grade 2.

- Known HIV infection or chronic hepatitis B or C (the safety and effectiveness of
sorafenib in this patient population have not been studied).

- Previous or concurrent cancer that is distinct in primary site or histology from
breast cancer EXCEPT cervical cancer in-situ, treated basal cell carcinoma,
superficial bladder tumors [Ta and Tis] or any cancer curatively treated > 5 years
prior to randomization.

- Known or suspected allergy to sorafenib or gemcitabine/capecitabine.

- Prior or concurrent use of St. John's Wort or rifampin (rifampicin) within 3 weeks of
randomization.

- Concurrent anti-cancer therapy other than gemcitabine/capecitabine and
sorafenib/placebo.

- Prior treatment with any agent that targets VEGF or VEGFR (licensed or
investigational), except bevacizumab.

- Women who are pregnant or breast-feeding.

- Use of any investigational drug within 30 days or 5 half-lives, whichever is longer,
preceding randomization.

- Inability to comply with protocol and/or not willing or not available for follow-up
assessments.

- Any condition which in the investigator's opinion makes the patient unsuitable for
the study participation.