Inclusion Criteria:

- Durie-Salmon stage IIA-IIIB multiple myeloma

- Age > 18 and ≤ 65 years

- Previously untreated myeloma

- Presence of a sibling (potential donor)

- Bilirubins < twice normal;ALAT and ASAT < four times normal

- Left ventricular ejection fraction > 40%

- Creatinine clearances > 40 mL/min

- Pulmonary dysfunction with diffusing capacity for carbon monoxide (DLCO) > 40% and/or
need for continuous oxygen supplementation

- Karnofsky performance status > 60%

- Patients must give written informed consent

Exclusion Criteria:

- Age > 65 years

- Previously treated myeloma

- Absence of a sibling (genetic randomisation cannot be applied)

- Karnofsky performance status score < 60%

- HIV-infection

- Pregnancy

- Refusal to use contraceptive techniques during and for 12 months following treatment

- Patients unable to give written informed consent

- PS. Informed consent is obtained from each patient according to the Institutional
Review Boards of the participating centers. The study is conducted according to the
Declaration of Helsinki.