The present study will be a multicenter, prospective phase II-study investigating safety and efficacy of the combination of auto-allo tandem stem cell transplantation in patients with multiple myeloma and age of >_60 years, followed by maintenance therapy with low-dose Thalidomide and Donor Lymphocyte Infusions.

Inclusion Criteria:

• Multiple Myeloma Stage II or III acc. to Salmon and Durie
• Patient's age 18-60 years
• Patient's written informed consent
• Women and men capable of reproduction must agree to use adequate contraceptive measures (condom, IUD, oral contraceptives) until three months after termination of treatment
• a maximum of eight chemotherapy cycles prior to registration (CR/ PR/ MR/ or PD)

Exclusion Criteria:

• More than eight chemotherapy cycles prior to registration

• severe irreversible renal, hepatic, pulmonary or cardiac disease, such as

  • total bilirubin, SGPT or SGOT > 3 times upper the normal level
  • Left ventricular ejection fraction < 30 %
  • Creatinine Clearance < 30 ml/min
  • DLCO < 35 % and/or receiving supplementary continuous oxygen

• Positive serology for HIV

• Pregnant or lactating women

• Participation in another trial at the time of registration

• Preceding autologous stem cell transplantation

• age > 61 years