Key

Inclusion Criteria:

- Confirmed diagnosis of multiple myeloma with measurable disease

- Evidence of relapsed or refractory disease and at least 2 prior therapies for
multiple myeloma

- Eastern Cooperative Oncology Group Performance Status of 0 - 2

- Last treatment for multiple myeloma not within 21 days prior to study treatment
initiation

- Bone marrow transplant not within 3 months prior to study treatment initiation

- Required baseline hematology and chemistry parameters.

Key Exclusion Criteria:

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

- Abnormal QT interval corrected for heart rate using Fridericia's formula prolonged
(>450 msec) after electrolytes have been corrected on baseline electrocardiogram

- Malabsorption syndrome or uncontrolled gastrointestinal toxicities

- Dementia, chronic medical or psychiatric condition, or laboratory abnormality that
may increase the risk associated with study participation

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

- Clinically significant coagulation or platelet function disorder

- Intolerance to dasatinib and/or bortezomib

- Acute diffuse infiltrative pulmonary disease

- Prior or concurrent malignancy, except for adequately treated basal cell or squamous
cell skin cancer, adequately treated Stage I or II cancer currently in complete
remission, cervical carcinoma in situ, or any other cancer from which the participant
has been disease-free for 3 years.