Eribulin Mesylate as Second-Line Therapy for Locally Advanced, Unresectable, or Metastatic Pancreatic Cancer Patients

Inclusion Criteria: * Histologically/cytologically confirmed pancreatic carcinoma (locally advanced, unresectable or metastatic) * measurable disease (at least 1 lesion accurately measured in at least 1 dimension (longest diameter as \>20mm with conventional techniques or \>10mm with spiral CT scan) * \>=4 weeks from any major surgery * Up to 1 prior line of gemcitabine based systemic therapy (single agent/combination therapy) for locally advanced/metastatic disease with evidence of disease progression. Prior therapy with inhibitors of angiogenesis and/or the epidermal growth factor receptor permitted. Last chemotherapy dose \>=4 weeks prior to randomization. * May have received prior 5FU (+/- folinic acid)/gemcitabine given concurrently with radiation as a "radiation sensitizer". Last chemotherapy dose \>=4 weeks prior to randomization. * Prior radiation treatment \>=4 weeks prior to randomization * Age \>18 years. * Life expectancy \>=3 months * ECOG\< 2(Karnofsky-60%) * leukocytes\>3,000/mcL * absolute neutrophil count\>1,500/mcL * platelets\>100,000/mcL * total bilirubin \< 1.5 UNL * AST/ALT≤2.5x institutional ULN * creatinine within institution limits OR creatinine clearance\>60mL/min/1.73m2 for patients with creatinine levels above institution limits * concurrent use of inhibitors/inducers of CYP3A4 are prohibited during the study treatment period * effects of E7389 on developing human fetus are unknown. Women of childbearing potential and men must agree to use adequate contraception (hormonal or barrier method of birth control; abstinence) prior to study entry and for the duration of study participation * Ability to understand/willingness to sign written informed consent Exclusion Criteria: * chemotherapy/radiotherapy within 4 weeks (6 weeks for nitrosoureas or mitomycin C) prior to entering study or those who have not recovered from adverse events due to agents administered more than 4 weeks earlier * May not be receiving other investigational agents * Known brain metastases * History of allergic reactions attributed to compounds of similar chemical or biologic composition to E7389 * Uncontrolled intercurrent illness including but not limited to ongoing or active infection, symptomatic congestive heart failure, unstable angina pectoris, cardiac arrhythmia, or psychiatric illness/social situations that would limit compliance with study * Pregnant women excluded because E7389 is an antitubulin agent with the potential for teratogenic/abortifacient effects * HIV-positive patients on combination antiretroviral therapy are ineligible because of potential for p PK interactions with E7389 * Other active malignancies in past 5 years except for cervical carcinoma in situ and non-melanomatous skin cancer