This is a Prospective Phase II Study to evaluate Cord Blood Transplantation in Inherited or Acquired Severe Aplastic Anemia Refractory or in Relapse after Immunosuppressive Therapy in the absence of an HLA identical donor;

This is a Prospective Phase II Study to evaluate Cord Blood Transplantation in Inherited or Acquired Severe Aplastic Anemia Refractory or in Relapse after Immunosuppressive Therapy in the absence of an Human Leucocyte Antigen (HLA) identical donor; 26 patients will be recruited, according to a one step Fleming design

Inclusion Criteria:

• Age: 3-55 years old
• inherited aplastic anemia (with severe aplastic anemia criteria) or acquired aplastic anemia in relapse or treatment failure after immunosuppressive therapy without clonal evolution
• Karnovsky Index >= 60%
• Informed consent

Exclusion Criteria:

• HLA identical donor