Analyze the results of ASCT using intravenous Busulfan and Melphalan as conditioning regimen for patients with Multiple Myeloma.

Primary Efficacy and safety of the procedure in terms of number of remissions, survival, event-free survival, relapse risk, and early transplant-related mortality (up to day +100).

Secondary Graft kinetics (time to neutrophil and platelet recovery after ASCT) 2.Analyze the presence of transplant-related complications (infections, sinusoidal occlusive syndrome and others) 3.Analyze prognostic factors for engraftment, remission rate, relapse risk, disease-free and overall survival after ASCT

Inclusion Criteria:

• Symptomatic multiple myeloma
• Male or female subject age >= 70 years
• The subject has received at least one previous line of therapy including:
• Front-line treatment with VBMCP/VBAD or VAD or second-line therapy with regimens including bortezomib, thalidomide or lenalidomide
• The subject has given voluntary written informed consent

Exclusion Criteria:

• Use of bortezomib, thalidomide or lenalidomide as front-line therapy
• ECOG satus >=2
• Left ventricular ejection fraction <40%
• DLCO and FVC <39% theoretical value
• Abnormal liver function(total bilirubin > 2 mg/dL and/or ALT or AST > 3 x ULN)
• Serum creatinine at transplant >1.6 mg/dL and/or creatinine clearance < 65 mL/minute
• Subject has an active systemic infection requiring treatment
• Subject had a myocardial infarction within 6 months of enrollment or has NYHA Class III or IV heart failure, uncontrolled angina, severe uncontrolled ventricular arrythmias
• Subject has any other serious medical condition (severe hepatic impairment, pericardial disease, acute diffuse infiltrative pulmonary disease) or psychiatric illness that could potentially interfere with the completion of treatment of this protocol
• Subject is known to be immunodeficiency virus (HIV)-positive
• Subject has received an experimental drug or used and experimental medical device within 4 weeks before enrollment
• If female, the subject is pregnant or breast-feeding. Confirmation that the subject is not pregnant must be established by a negative pregnancy test at screening. Pregnancy testing is not required for postmenopausal or surgically sterilized women