Inclusion Criteria:

1. Cytopathologically or histologically confirmed diagnosis of multiple myeloma
previously requiring systemic treatment.

2. Evidence of relapsed or refractory disease as documented from the prior treatment
history. (Refractory myeloma is defined as disease that is non-responsive while on
salvage therapy, or progresses within 60 days of last therapy. Relapsed myeloma is
defined as previously treated myeloma which after a period of being off-therapy
requires the initiation of salvage therapy. Detailed definitions provided in the
PTS-1)

3. Have received at least 2 prior treatment regimens for multiple myeloma including
chemotherapy, autologous transplantation, immunotherapy, or other investigational
agents. Pre-planned induction, followed by transplant and maintenance should be
considered as one regimen.

4. Presence of measurable disease as defined by at least one of the following;

- Serum M-protein ≥ 1g/dL (measurable disease)

- Urine M-protein ≥ 200mg/24 hours by protein electrophoresis (measurable disease)

Exclusion Criteria:

1. Patients with non-secretory, or oligosecretory, multiple myeloma.

2. Patients with symptomatic amyloidosis, or with plasma cell leukemia.

3. Patients who have received allogeneic stem cell transplantation and who show evidence
of active graft-versus-host disease that requires immunosuppressive therapy.

Other protocol-defined inclusion/exclusion criteria may apply