This is an international multi-center prospective, double randomized, open, controlled phase III study with a phase II entrance phase to compare the therapeutic efficacy of thalidomide plus dexamethasone to conventional melphalan plus prednisone in newly diagnosed myeloma patients.

Inclusion Criteria:

• Patients with Multiple Myeloma of IgG, IgA, IgD, IgE, IgM lambda or kappa light chain, low secretory or non-secretory disease
• WHO performance status 0,1,2,or 3
• No prior treatment of multiple myeloma
• Clear requirement of treatment (usually Durie/Salmon stage II or III)
• Anticipated life expectancy of at least 3 months
• Adequate organ function
• Minimum recovery period of 2 weeks following any major surgical procedure before entry into this study
• Women, who are sterilized via hysterectomy or bilateral tubal ligation or at least one year post-menopausal
• Age of at least 19 years, there is no upper age limit patients must have been informed and must have signed an informed consent

Exclusion Criteria:

• Extramedullary plasmocytoma or solitary plasmocytoma without evidence of dissemination of disease
• Benign monoclonal gammopathy
• Multiple myeloma of IgM without osteolytic bone lesions
• Smouldering myeloma
• More than 3 irradiation fields
• Irreversible performance status of WHO4
• Prior treatment of myeloma with any of the following: chemotherapeutic or immunomodulatory agents, corticosteroids, antiangiogenic agents or other investigational drugs
• Women of childbearing potential
• Preexisting peripheral polyneuropathy
• Congestive heart failure NYHA III, IV
• Acute infection requiring systemic antibiotics at study entry until resolved
• Any uncontrolled underlying medical condition (eg diabetes, glaucoma)
• Second primary malignancy (with the exception of cervical carcinoma in situ and non-myeloma skin malignancies) unless patient has been disease-free for at least three years