Bendamustine Hydrochloride, Pomalidomide, and Dexamethasone in Treating Patients with Relapsed or Refractory Multiple Myeloma

Inclusion Criteria

• Cytopathologically or histologically confirmed diagnosis of multiple myeloma
• Relapsed or refractory to the most recently received therapy; refractory disease is defined as =< 25% response or progression during therapy or within 60 days after completion
• All patients must have received prior lenalidomide therapy and been determined to be refractory; refractory will be defined as a history of progression on a regimen containing full or maximally tolerated dose of lenalidomide administered for a minimum of at least two completed cycles of therapy
• Measurable disease, as indicated by one or more of the following: * Serum M protein >= 0.5 g/dL * Urine Bence Jones protein > 200 mg/24 hr * Elevated free light chain as per International Myeloma Working Group (IMWG) criteria, and abnormal ratio
• Prior to enrollment, sites must provide evidence of myeloma progression/relapse and evidence of being refractory to lenalidomide, with start and stop dates of lenalidomide therapy and the most recent treatment regimen, as well as best tumor response to all prior treatment regimens
• Life expectancy of more than 3 months
• Eastern Cooperative Oncology Group (ECOG) performance status of 0-2
• Total bilirubin =< 2 times the upper limit of normal (ULN)
• Aspartate aminotransferase (AST) and alanine aminotransferase (ALT) =< 3 times ULN
• Serum creatinine =< 3 mg/dL
• Absolute neutrophil count (ANC) >= 1.0 x 10^9/L or < 1.0 x 10^9/L but >= 0.75 due to > 30% marrow involvement * Patients who entered the trial prior to June 4, 2014 were restricted to > 50% marrow involvement
• Hemoglobin >= 8 g/dL (transfusion permitted)
• Platelet count >= 75.0 x 10^9/L or =< 75.0 x 10^9/L but >= 50.0 x 10^9/L due to > 30% marrow involvement * Patients who entered the trial prior to June 4, 2014 were restricted to > 50% marrow involvement
• Screening ANC should be independent of granulocyte and granulocyte/macrophage colony stimulating factor (filgrastim [G CSF] and sargramostim [GM CSF]) support for at least 1 week and of pegylated G CSF for at least 2 weeks
• Patients may receive red blood cell (RBC) or platelet transfusions, if clinically indicated, in accordance with institutional guidelines
• Screening platelet count should be independent of platelet transfusions for at least 1 week
• Patients must agree to take enteric coated aspirin 81 mg orally daily, or if history of prior thrombotic disease, must be fully anticoagulated with warfarin (international normalized ratio [INR] 2-3) or be treated with full dose, low molecular weight heparin, as if to treat deep venous thrombosis (DVT)/pulmonary embolism (PE)
• Written informed consent in accordance with federal, local, and institutional guidelines
• Females of childbearing potential (FCBP) must have a negative serum or urine pregnancy test with a sensitivity of at least 25 mIU/mL within 10 –– 14 days prior to and again within 24 hours of starting pomalidomide and must either commit to continued abstinence from heterosexual intercourse or begin TWO acceptable methods of birth control, one highly effective method and one additional effective method AT THE SAME TIME, at least 28 days before she starts taking pomalidomide; FCBP must also agree to ongoing pregnancy testing
• Male patients must agree to never have unprotected sexual contact with a female who can become pregnant and must agree to either completely abstain from sexual contact with females who are pregnant or are able to become pregnant, or he must use a latex condom every time he engages in sexual contact with females who are pregnant or may become pregnant while he is taking pomalidomide and for 1 week after he stops taking the drug, even if he has had a successful vasectomy; the patient must agree to inform his physician if he has had unprotected sexual contact with a female who can become pregnant or if he thinks for any reason that his sexual partner may be pregnant; male patients cannot donate semen or sperm while taking pomalidomide and for at least 1 week days after completing the study
• All study participants must be registered into the mandatory POMALYST REMS program, and be willing and able to comply with the requirements of the POMALYST REMS program

Exclusion Criteria

• Patients with known sensitivity to any immunomodulatory drugs (IMiDs)
• Use of any other experimental drug or therapy within 21 days of study-related drug therapy
• Exposure to any prior chemotherapy or steroid use within 14 days of study-related drug therapy; (steroid use is allowed if necessary to treat spinal cord compression)
• Any prior use of pomalidomide
• Radiation therapy within 14 days of screening
• POEMS syndrome (polyneuropathy, organomegaly, endocrinopathy, monoclonal protein, and skin changes)
• Plasma cell leukemia
• Waldenstrom’s macroglobulinemia
• Major surgery within 21 days prior to first dose
• Pregnant or lactating females
• Congestive heart failure (New York Heart Association class III to IV), symptomatic ischemia, conduction abnormalities uncontrolled by conventional intervention or myocardial infarction in the previous six months
• Uncontrolled hypertension
• Acute infection requiring systemic antibiotics, antivirals, or antifungals within 14 days prior to first dose
• Patients receiving active treatment or intervention for any other malignancy or patients who, at the investigator’s discretion, may require active treatment or intervention for any other malignancy within 8 months of starting study treatment
• Serious psychiatric or medical conditions that could interfere with treatment
• Significant neuropathy (grade 3, grade 4) at the time of the first dose and/or within 14 days before enrollment
• Contraindication to any of the required concomitant drugs, including proton pump inhibitor (e.g. lansoprazole), enteric coated aspirin or if a history of prior thrombotic disease, warfarin or low molecular weight heparin
• Patients with primary systemic amyloidosis