Treatment of Brain Metastases From Breast Cancer With Eribulin Mesylate

Primary Objectives:

To determine the 3-month central nervous system (CNS)-progression free survival (PFS) for
patients with metastatic breast cancer with brain metastases treated with eribulin mesylate.

Secondary Objective(s):

1. Estimate CNS complete and partial response rates (CR and PR) and duration of CNS response
in this patient population.

2 Evaluate toxicity in patients with breast cancer with brain metastases treated with
eribulin mesylate.

3 Estimate clinical benefit rate (CBR) at 3 months in breast cancer patients with brain
metastases treated with eribulin mesylate. (CBR is the sum of CR, PR and stable disease at 3
months).

4 To estimate systemic disease (extra cranial) response rate and duration of systemic
response in this patient population.

5 Overall survival in this patient population.

Design:

This is a phase II study that will require patients to evaluate the primary objective (CNS
PFS at 3 months). Study patients will have a baseline brain MRI and a second MRI at 12 weeks
to evaluate disease.

Inclusion Criteria:

- Female with histologically confirmed breast cancer.

- Patients must have evidence of metastatic disease (non measurable disease is
eligible).

- Radiologically confirmed metastatic brain lesion by MRI.

- Brain metastases from breast cancer with or without prior WBRT, STS of surgical
resection. Progression must be documented in an at least one lesion untreated by SRS
or in any site after surgery or WBRT.

- Patients must be neurologically stable and with stable dose steroids and
anticonvulsants for at least 1 week prior to obtaining the baseline MRI of the brain,
and/or at least 1 week prior to beginning study treatment.

- No presence of uncontrolled systemic disease or tumor related complication which, in
opinion of the investigator, might restrict life expectancy to less than 3 months.

- Patients may not be on any cytotoxic chemotherapy or hormonal treatment for breast
cancer during protocol treatment. Trastuzumab is allowed in HER2 positive patients).

- Able to comprehend and willing to sign an Informed Consent Form (ICF)

- Karnofsky performance status ≥ 60

- No brain radiation therapy > 4 weeks

- No chemotherapy for > 3 weeks before planned start of protocol treatment

- Adequate bone marrow, renal, and hepatic function, per local reference laboratory
ranges as follows:

- Absolute neutrophil count (ANC) ≥ 1,500/mm3

- Platelet count ≥ 100,000/mm3

- Hemoglobin ≥ 9 g/dL

- Calculated creatinine clearance (CrCl) ≥ 30mL/min (Cockcroft-Gault method)

- Patients with normal, mild or moderate hepatic dysfunction are eligible.

- Calcium <10.1 mg/dL (corrected to serum albumin as follows: Corrected Calcium =
(0.8 x (4 - patient albumin)) + serum Ca

- Females of child-bearing potential must have a negative pregnancy test at screening
and agree to take appropriate precautions to avoid pregnancy (double barrier method of
birth control or abstinence) from screening through 3 months after the last dose of
treatment

- Able to undergo MRI evaluation with and without gadolinium contrast

Exclusion Criteria:

- Patients with the presence of an active infection, abscess or fistula

- Known leptomeningeal disease or CNS midline shifts.

- Any evidence of severe or uncontrolled systemic disease such as clinically significant
cardiovascular, pulmonary, hepatic, renal or metabolic disease.

- Severe conduction abnormality including significant QTc prolongation >450ms.

- Patients with grade 3/4 peripheral neuropathy.

- Patients with pacemaker or an ICD devices.

- Previous treatment with eribulin mesylate.