Inclusion Criteria:

- Newly diagnosed symptomatic multiple myeloma (MM) patient

- Aged under 65

- Candidate for ASCT, with measurable levels of paraprotein in the serum (³ 10 g/L) or
the urine (³ 200 mg/day)

- Using effective contraceptive methods (for fertile men, women of childbearing
potential)

- Provision of informed consent

- No evidence of active infection

Exclusion Criteria:

- Asymptomatic MM

- Non-secretory MM

- Aged 66 years or over

- ECOG performance status over 2 (see Appendix 2)

- Proven amyloidosis

- A personal medical history of cancer (except for basocellular skin cancer or in situ
cervical cancer)

- Positive HIV serology

- A personal medical history of severe psychiatric disease

- Severe diabetes contraindicating the use of high-dose dexamethasone

- NCI grade ³ 2 peripheral neuropathy

- Serum clinical chemistry:

- creatinine level > 300 µmol/L or requiring dialysis

- bilirubin, transaminases or GamaGT > 3 the upper normal limit (UNL)

- Prior or current systemic therapy for MM, including steroids (except for emergency
use of a 4-day block of dexamethasone between the screening phase and randomization)

- Radiation therapy in the 2 weeks preceding randomization

- A personal medical history of allergic reactions to compounds containing boron or
mannitol

- Non-controlled or severe cardiovascular disease (including a myocardial infarction in
the 6 months prior to recruitment) or NYHA class III or IV renal failure

- Use of any investigational drug in the 30 days preceding randomization

- Pregnant or lactating women; a serum Beta-hCG pregnancy test must be performed during
the screening phase for female patients of childbearing potential

- Severe pulmonary troubles (including acute infiltrative pneumopathy)