Inclusion Criteria:

- The patient has relapsed or refractory multiple myeloma that has progressed following
at least one (1) prior therapy.

- The patient has measurable disease defined as one of the following:

serum M-protein >=1 g/dL urine M-protein >=200 mg/24 hours

- Must have received at least one (1) prior line of systemic treatment that may have
included lenalidomide and/or an anthracycline.

- No cytotoxic chemotherapy within 4 weeks prior to first dose of amrubicin. NOTE: this
interval may be reduced to 14 days for thalidomide, lenalidomide, bortezomib or
corticosteroids, provided other entry criteria are met.

- Age >= 18 at the time of consent.

- The patient has a life expectancy of more than >= months.

- No known central nervous system involvement by myeloma.

- ECOG performance status 0-1 at study registration during phase I. Once safety is
confirmed, ECOG performance status 0-2 at study registration during phase II.

- No poorly controlled intercurrent illness.

- Platelets >100 x 10^9/L, Hemoglobin > 8.0g/dL and ANC >1.5 x 10^9/L

- AST and ALT <= x upper limit of normal (ULN), total bilirubin <= 1.5 x ULN

- Calculated creatinine clearance >= 50 ml/min by Cockcroft-Gault formula.

- Left ventricular ejection fraction (LVEF) >=50% by Echocardiogram (ECHO) or multiple
gate acquisition scan (MUGA)

- All study participants must be registered into the mandatory RevAssist program, and
be willing and able to comply with the Requirements of RevAssist.

- Disease free of prior malignancies for >= 5 years with exception of currently treated
basal cell, squamous cell carcinoma of the skin, or carcinoma "insitu" of the cervix
or breast.

- Females of childbearing potential (FCBP) must have a negative serum or urine
pregnancy test with a sensitivity of at least 50 mIU/mL within 10 - 14 days and again
within 24 hours prior to prescribing lenalidomide for Cycle 1 (prescriptions must be
filled within 7 days) 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 lenalidomide. FCBP must also agree to ongoing
pregnancy testing. Men must agree to use a latex condom during sexual contact with a
FCBP even if they have had a successful vasectomy. See Appendix: Risks of Fetal
Exposure, Pregnancy Testing Guidelines and Acceptable Birth Control Methods.

- Ability to understand and the willingness to sign a written informed consent
document.

- Able to adhere to the study visit schedule and other protocol requirements.

- Able to take aspirin (81 or >=25 mg) daily as prophylactic anticoagulation Patients
intolerant to ASA may use warfarin or low molecular weight heparin (LMWH). Patients
with previous thromboembolic event on lenalidomide or thalidomide may be started on
warfarin or LMWH. Patients already taking warfarin or LMWH do not require additional
aspirin.

Exclusion Criteria:

- Any serious medical condition, laboratory abnormality, or psychiatric illness that
would prevent the subject from signing the informed consent form.

- Pregnant or breastfeeding females. (Lactating females must agree not to breast feed
while taking lenalidomide).

- Any concurrent severe or uncontrolled medical disease which places the subject at
unacceptable risk if he/she were to participate in the study or confounds the ability
to interpret data from the study.

- Use of any other experimental drug or therapy within 28 days of first dose of
amrubicin.

- Known hypersensitivity to thalidomide or lenalidomide.

- The development of erythema nodosum if characterized by a desquamating rash while
taking thalidomide or similar drugs.

- LVEF <=50%.

- Concurrent use of other anti-cancer agents or treatments.

- Known positive for HIV, or infectious hepatitis, type B or C.

- Cranial radiotherapy <= 21 days prior to first dose of amrubicin; radiotherapy to all
other areas <= 7 days prior to first dose of amrubicin.