4. Have a documented diagnosis of multiple myeloma and have relapsed and refractory disease. Subjects must have received at least 2 prior therapies. Subjects must have relapsed after having achieved at least stable disease for at least one cycle of treatment to at least one prior regimen and then developed progressive disease(PD). Subjects must also have documented evidence of progressive disease(PD) during or within 60 days (measured from the end of the last cycle) of completing treatment with the last antimyeloma drug regimen used just prior to study entry (refractory disease).