Study of the Safety and Efficacy of an Investigational Drug in Adult Patients With Multiple Myeloma

Other specific inclusion/exclusion criteria may apply. In order to determine eligibility, further examination by the investigator is necessary. Inclusion Criteria: * Eligible patients must be at least 18 years of age with a diagnosis of multiple myeloma including elevated M-blood/urine protein or a tumor that can be evaluated by the doctor during the investigational drug's treatment. * The patient's multiple myeloma must have gotten worse during/after previous chemotherapy was given. * Any side-effects from prior chemotherapy must have subsided * Blood and urine tests must show adequate bone marrow, liver, and kidney function. Exclusion Criteria: Any of the following will exclude patients from study participation: * indolent or smoldering myeloma or localized plasmacytoma * hyperviscosity syndrome * irradiation to 25% or more of bone marrow * prior high dose chemotherapy with bone marrow or stem cell support * current participation in other clinical trials * pregnant or breast-feeding women * known HIV-positive or AIDS-related illness * patients planning to have radiation therapy or surgery that would interrupt study therapy in the next 6 months.