Inclusion Criteria:

1. Fulfilled criteria for diagnosis of either moderate (mAA) or severe aplastic anemia
(sAA) at the time of initial diagnosis defined per protocol.

2. Patient with a history sAA must have had an incomplete response at least 3 months
following treatment with ATG/CsA, or they must have relapsed following an initial
response to treatment.

3. Patient must not be receiving any cyclosporine or any other T cell immunosuppressive
agents within 4 weeks of study entry.

4. Patients must have organ function as defined below:

- total bilirubin within normal institutional limits (NV: 0.0-1.5 mg/dL)

- AST(SGOT)/ALT(SGPT) <2.5 X institutional upper limit of normal AST (NV: 7-40
U/L); ALT (NV: Male 5-50 U/L; Female 0-45 U/L)

- creatinine within normal institutional limits (NV: Age 18 0.4-1.3 mg/dL; 19-99
years old 0.7-1.4 mg/dL) OR

- creatinine clearance >60 mL/min/1.73 m2 for patients with creatinine levels
above institutional normal.

5. Peripheral blood counts at the time of enrollment must include at least one of the
following: Hgb <9 g/dL or red blood cell (RBC) transfusion dependence, ANC <1000/µl,
or platelet count of <60,000/µL.

6. Women of child-bearing potential and men must agree to use adequate contraception
defined per protocol.

7. Ability to understand and the willingness to sign a written informed consent
document.

Exclusion Criteria:

1. Patients may not be receiving any other investigational agents (other than
hematopoietic growth factors) within 4 weeks of study entry.

2. History of allergic reactions attributed to compounds of similar chemical or biologic
composition to Alefacept.

3. Current diagnosis of acute myeloid leukemia (AML), myelodysplastic syndromes (MDS),
Fanconi's anemia, Dyskeratosis Congenita (DC) or other hereditary forms of AA.

4. Psychiatric, addictive or any other disorder that compromises ability to give a truly
informed consent.

5. Age <18 years.

6. ECOG performance status >2 (Karnofsky <60%, see Appendix A).

7. Malignancy other than non-melanoma skin cancer within the last 2 years.

8. Uncontrolled intercurrent illness including, but not limited to, ongoing or active
infection (defined as uncontrolled infection requiring IV antibiotics, invasive
fungal infection and progressive CMV viremia), symptomatic congestive heart failure
(NYH class III and IV), unstable angina pectoris, or cardiac arrhythmia.

9. Pregnant or breastfeeding women.

10. HIV-positive patients on combination antiretroviral therapy.

11. Patients who have previously received systemic chemotherapy and/ or radiation
therapy.

12. Patients who previously underwent allogeneic hematopoietic stem cell transplant.