Fludarabine, Busulfan, Antithymocyte Globulin, and Donor Stem Cell Transplant in Treating Patients With Multiple Myeloma That Has Not Responded to Treatment

OBJECTIVES:

Primary

• To study the toxicity of reduced intensity conditioning comprising fludarabine phosphate, busulfan, and anti-thymocyte globulin followed by allogeneic hematopoietic stem cell transplantation in patients with refractory or relapsed multiple myeloma.

Secondary

• To study the tumor response in these patients.
• To study the incidence of acute or chronic graft-versus-host disease in these patients.
• To study the incidence of infectious complications in these patients.
• To study relapse- or progression-free and overall survival of these patients.
• To study the biological mechanisms (i.e., taking graft, immunological recovery, antitumor activity, and chimerism).

OUTLINE: This is a multicenter study.

Patients receive reduced intensity conditioning comprising fludarabine IV on days -5 to -1, oral busulfan on days -4 and -3, and anti-thymocyte globulin IV on days -2 and -1. Patients undergo allogeneic hematopoietic stem cell transplantation on day 0.

After completion of study therapy, patients are followed every month for 6 months and then every 3 months for 1½ years.

DISEASE CHARACTERISTICS:

• Diagnosis of multiple myeloma, meeting 1 of the following criteria:

• Stage I disease with a bone lesion
• Stage II or III disease meeting any of the following criteria:

• Elevated beta-2 microglobulin
• Deletion of chromosome 13
• Refractory or relapsed disease
• Presence of an evaluable monoclonal component
• Must have achieved reduction of primary tumor after receiving prior intensified chemotherapy with high-dose melphalan and cyclosporine with autologous transplantation
• HLA identical family donor available

• Bone marrow transplantation is allowed in case hematopoietic stem cell collection fails

PATIENT CHARACTERISTICS:

• Karnofsky 70-100%
• No contraindications to allogeneic transplantation
• No contraindications to drugs used in conditioning regimen
• No psychiatric illness
• No other cancer within the past 5 years except basal cell skin cancer or epithelioma in situ of the cervix
• No serious and uncontrolled infection
• Not pregnant or nursing
• Fertile patients must use effective contraception

PRIOR CONCURRENT THERAPY:

• See Disease Characteristics
• At least 1 month since participation in another prior clinical trial