Melphalan and Stem Cell Transplant Before Total-Body Irradiation and Donor Stem Cell Transplant in Treating Patients With Stage I-III Multiple Myeloma

PRIMARY OBJECTIVES:

I. To evaluate engraftment of human leukocyte antigen (HLA) identical peripheral blood stem
cell (PBSC) allografts given after conditioning with total-body irradiation (TBI) (200 cGy)
and post-grafting immunosuppression with cyclosporine (CSP)/mycophenolate mofetil (MMF) in
myeloma patients initially cytoreduced with high-dose melphalan.

II. To evaluate non-relapse mortality at day 100 post allografting. III. To evaluate the
efficacy of this allografting strategy in terms of long-term progression free survival (PFS).

OUTLINE:

CONDITIONING REGIMEN: Patients receive high-dose melphalan intravenously (IV) over 15-20
minutes on day -2.

TRANSPLANTATION: Patients undergo autologous bone marrow or PBSC transplantation (PBSCT) on
day 0.

NON-MYELOABLATIVE CONDITIONING REGIMEN: Beginning 40-120 days after autologous transplant,
patients undergo TBI on day 0.

TRANSPLANTATION: Patients undergo donor PBSCT on day 0.

IMMUNOSUPPRESSION: Patients receive cyclosporine IV twice daily (BID) on days -1 and 0 and
orally (PO) BID on days 1-80 with taper based on evaluation of disease response and
graft-versus-host disease (GVHD). Patients also receive mycophenolate mofetil PO BID on days
0-27.

POST-TRANSPLANTATION DONOR LYMPHOCYTE INFUSION (DLI): Beginning 4 weeks after
immunosuppression, patients achieving persistent or progressive disease may undergo DLI over
30 minutes every 4 weeks for up to 3 treatments.

After completion of study treatment, patients are followed up for 3 years.

Inclusion Criteria:

- Meet Salmon and Durie criteria for initial diagnosis of multiple myeloma; transplant
will be offered to patients with stage II or III multiple myeloma (MM) at diagnosis or
have received chemotherapy and/or radiation therapy for progressive MM after initial
diagnosis of stage I disease

- The patient must have the capacity to give informed consent

- Have received at least 4 cycles of conventional dose chemotherapy for MM

- DONOR: HLA genotypically identical sibling

- DONOR: Donor must consent to filgrastim (G-CSF) administration and leukapheresis for
both peripheral blood stem cell (PBSC) allograft and subsequent DLI

- DONOR: Donor must have adequate veins for leukapheresis or agree to placement of
central venous catheter (femoral, subclavian)

- DONOR: Age < 75, older donors may be considered after consultation by Psychological
Consultation Center (PCC)

Exclusion Criteria:

- Karnofsky score less than 60, unless due solely to myeloma

- Left ventricular ejection fraction less than 40%

- Bilirubin greater than 2 X the upper limit of normal

- Serum glutamic pyruvic transaminase (SGPT) and serum glutamic oxaloacetic transaminase
(SGOT) > 2 X the upper limit of normal

- Diffusion lung capacity of carbon monoxide (DLCO) < 50% (corrected) or receiving
continuous supplemental oxygen

- Patients with poorly controlled hypertension

- Pregnancy

- Seropositive for the human immunodeficiency virus

- Fertile men or women unwilling to use contraceptive techniques during and for 12
months following treatment

- Creatinine clearance < 40 cc/min at the time of initial autografting evaluation

- Prior autograft (can be treated on alternative protocol)

- DONOR: Identical twin

- DONOR: Age less than 12 years

- DONOR: Pregnancy

- DONOR: Infection with human immunodeficiency virus (HIV)

- DONOR: Inability to achieve adequate venous access

- DONOR: Known allergy to G-CSF

- DONOR: Current serious systemic illness

- DONOR: Failure to meet Fred Hutchinson Cancer Research Center (FHCRC) criteria for
stem cell donation as described in the standard practice guidelines of the institution