Study of Bendamustine, Lenalidomide and Low-dose Dexamethasone, for the Treatment of Patients With Relapsed Myeloma

Inclusion Criteria:

* Voluntary written informed consent
* Men and women age ≥ 18 years
* Female subjects are either post-menopausal or surgically sterilized or willing to use 2 simultaneous methods of contraception
* Male patients must agree to use a latex condom during sexual contact with females of childbearing potential throughout the study and for at least 28 days following discontinuation of lenalidomide;
* Confirmed diagnosis of Multiple Myeloma with measurable disease .Patients with evidence of relapsed disease after more than 1 and equal but not more than 3 prior lines of therapy.
* ECOG Performance Status 0 - 2
* Required baseline haematology and chemistry parameters

Exclusion Criteria:

* Myocardial infarction within 6 months prior to enrollment or has NYHA class III or IV heart failure, uncontrolled angina, severe uncontrolled ventricular arrhythmias, or electrocardiographic evidence of acute ischemia or active conduction system abnormalities.
* Female subjects either pregnant or breast-feeding (negative serum β-human chorionic gonadotropin (β-hCG) pregnancy test result)
* Patients have received other investigational drugs with 14 days before enrollment.
* Serious medical or psychiatric illness likely to interfere with participation in this clinical study.
* Any of the following laboratory abnormalities:

Absolute neutrophil count (ANC) \<1,000 /μl (1x109 /L) Untransfused platelet count \< 50,0000cell/μl (50x109 /L) Serum SGOT/AST or SGPT/ALT \> 2.0 upper limit of normal (ULN) Total bilirubin \> 2.0 mg/dL Renal insufficiently (serum creatinine level \> 2.5 mg/dl or Creatinine clearance \< 30 mL/min calculated by Cockcroft-Gault estimation)

* Patients with active infections are ineligible.
* Patients who are HIV positive are ineligible.
* Patients with active leptomeningeal involvement are ineligible.
* Patients with a history of previous CSF tumor involvement without symptoms or signs are eligible provided the CSF is now free of disease on lumbar puncture, and MRI of the brain shows no tumor involvement.
* History of other malignancies within 3 years prior to study entry except for adequately treated carcinoma in situ of the cervix or basal or squamous cell skin cancer or breast, low grade, early stage localized prostate cancer treated surgically with curative intent (TNM stage of T1a or T1b),
* Patients with uncontrolled insulin-dependent diabetes mellitus or uncompensated major thyroid or adrenal dysfunction are ineligible.
* Patients with an ECOG performance status of \> 2 are ineligible.
* Malabsorption syndrome or uncontrolled gastrointestinal toxicities
* Clinically significant pleural effusion in the previous 12 months or current ascitis
* Clinically-significant coagulation or platelet function disorder
* Intolerance to bendamustine and/or lenalidomide