Inclusion Criteria:

- Patients ≤ 65 years old diagnosed with multiple myeloma in stage II or III of
Durie-Salmon staging.

- Patients who have achieved a complete response, partial after a myelosuppressive
chemotherapy treatment followed by infusion of peripheral blood progenitor cells as
first-line treatment. The criteria used to define the complete or partial response
are the EBMT, ABMTR IBMTR and set out in the criteria paper of Bladé J, Samson D,
Reece D, et al 1998

- Subjects must have a Karnofsky performance status ≥ 60% at the time of joining the
program.

- Subjects must have adequate renal and hepatic function, defined as <2 times the upper
limit of normal laboratory.

- Subjects must have adequate hematologic function, defined as: platelets> 50,000/μl,
≥Hemoglobin 9.0 g/dl, total leukocyte account> 2.000/μl

- No history of any cancer within the past 5 years except squamous cell carcinoma or
basal cell skin or cervical carcinoma in stage I or in situ.

- No history of hypersensitivity to interferon alfa or any other part of the injection.

- No severe clotting disorders, thrombophlebitis or pulmonary embolism, or
decompensated liver disease.

- Pregnant or lactating at the time of diagnosis can not participate in this
therapeutic program. During the same, men and women participants should not conceive
children. Also, women who become pregnant will be withdrawn from the protocol.

- Obtaining informed consent.

Exclusion Criteria:

- Patients > 65 years old.

- Patients with multiple myeloma stage I of Durie-Salmon staging system.

- Patients who have not achieved a complete or partial response after a
myelosuppressive chemotherapy regimen followed by infusion of progenitor cells from
peripheral blood autologous treatment of any kind is allowed intensification of
chemotherapy and pretransplant conditioning regimen. The criteria used to define the
complete or partial response are the EBMT, ABMTR IBMTR and set out in the criteria
paper of Bladé J, Samson D, Reece D, et al 1998

- Treatment with any investigational drug within 30 days prior to the addition to this
protocol.

- Subjects with severe cardiovascular disease.

- Subjects with a history of neuropsychiatric disorder that requires hospitalization.

- Subjects with thyroid dysfunction or uncontrolled diabetes mellitus (refractory to
treatment).

- Subjects with active infection and / or uncontrolled.

- Pregnant or lactating women or women of childbearing age not practicing effective
contraception.

- Patients with previous psychiatric disease, especially moderate or severe depression
or a history of severe psychiatric disorder, including psychosis, suicidal thoughts
or suicide attempts. In severe depression cover the following points: (a)
hospitalization for depression (b) electroconvulsive therapy for depression or (c)
depression leading to the prolonged absence at work or to alter significantly the
daily functions. Can be consider the entrance into the study of subjects with mild
depression, where it is demonstrated by pre-treatment assessment individual's
emotional state is clinically stable and in which case a treatment program formulated
for the patient who will become part of the patient's medical record.