Inclusion Criteria:

- Able to provide written informed consent

- Men and women age ≥ 18 years

- Confirmed diagnosis of multiple myeloma (MM) with measurable disease assessed within
1 month prior to treatment initiation

- Evidence of relapsed or refractory disease and at least one prior therapy for MM

- Eastern Cooperative Oncology Group Scale (ECOG) Performance Status of 0 - 2

- Last MM treatment at least 21 days prior to treatment initiation• Bone marrow
transplant (BMT) at least 3 months prior to treatment initiation

- Required baseline hematology and chemistry parameters

- Resolution of acute toxicity due to prior therapy to Grade <2 per National Cancer
Institute (NCI) Common Terminology Criteria for Adverse Events (CTCAE) Version 3.0

Exclusion Criteria:

- Women who are pregnant or breastfeeding

- Men whose sexual partners are women of child bearing potential (WOCBP) or WOCBP who
are unwilling or unable to use an acceptable method to avoid pregnancy for the entire
study period and for at least one month (4 weeks) before and for at least one month
(4 weeks) after the last dose of study medication.

- Clinically significant cardiac disease (New York Heart Association [NYHA] Class III
or IV)

- Abnormal corrected QT interval using Fridericia's formula (QTcF) interval prolonged
(> 450 msec)

- Medications that are generally considered to have a risk of causing "Torsades de
Pointes"

- Malabsorption syndrome or uncontrolled gastrointestinal toxicities

- Clinically significant pleural effusion in the previous 12 months or current ascites

- Clinically-significant coagulation or platelet function disorder

- Dementia, chronic medical or psychiatric condition, or laboratory abnormality

- Other severe, acute, or chronic medical or psychiatric condition or laboratory
abnormality, serious uncontrolled medical disorder or active infection

- Intolerance to dasatinib and/or lenalidomide

- Subjects with a history of severe rash, hypersensitivity reaction or anaphylaxis
related to prior thalidomide treatment