Inclusion Criteria:

- ECOG performance status of 0, 1, or 2

- Life expectancy of at least 12 weeks

- Histologic documentation of previously treated t(4;14)-positive multiple myeloma for
which no effective standard therapy exists

Exclusion Criteria:

- Prior use of any monoclonal antibody before study treatment

- Treatment with radiotherapy, thalidomide, lenalidomide, bortezomib, any
chemotherapeutic agent, or treatment with any other investigational anti-cancer agent
within 4 weeks of study treatment

- Completion of autologous stem cell transplant within 6 months prior to study
treatment

- Prior allogeneic stem cell transplant

- History of severe allergic or anaphylactic reactions to monoclonal antibody therapy

- Evidence of significant, uncontrolled concomitant diseases, including significant
cardiovascular disease or pulmonary disease

- Known active bacterial, viral, fungal, mycobacterial, parasitic, or other infection
at screening or any recent major episode of infection requiring treatment with IV
antibiotics or hospitalization prior to study treatment

- Recent major surgery (prior to study treatment), other than for diagnosis

- Presence of positive test results for Hepatitis B or Hepatitis C

- Known history of HIV seropositive status

- Women who are pregnant or lactating

- Childbearing potential without agreement to use effective form of contraception for
the duration of the study