RATIONALE: Immunosuppressive therapy may improve bone marrow abnormalities and may be an effective treatment for myelodysplastic syndrome.

PURPOSE: Phase II trial to study the effectiveness of antithymocyte globulin plus cyclosporine in treating patients who have myelodysplastic syndrome.

OBJECTIVES:

• Determine the response in patients with myelodysplastic syndromes treated with anti-thymocyte globulin and cyclosporine.
• Determine the frequency and severity of toxic effects of this regimen in these patients.
• Assess the correlation between response to treatment and the in vitro assessment of T-lymphocyte subsets in these patients.

OUTLINE: This is a multicenter study. Patients are stratified according to myelodysplastic syndrome subclassification (refractory anemia [RA] vs RA with ringed sideroblasts vs RA with excess blasts).

Patients receive induction therapy comprising anti-thymocyte globulin IV over 6-12 hours on days 1-4 and oral cyclosporine twice daily on days 5-94 followed by a taper until day 124. Patients who relapse after a response of at least 60 days may receive reinduction therapy comprising oral cyclosporine twice daily on days 1-90 followed by a taper until day 120. Treatment continues in the absence of disease progression or unacceptable toxicity.

Patients are followed monthly for 6 months, every 2 months for 2 years, and then every 6 months for 3 years.

PROJECTED ACCRUAL: A total of 130 patients (53 with refractory anemia [RA], 33 with RA with ringed sideroblasts, and 44 with RA with excess blasts) will be accrued for this study within 14-22 months.

• Leukemia
• Myelodysplastic Syndromes

• Biological: anti-thymocyte globulin
• Drug: cyclosporine

DISEASE CHARACTERISTICS:

• Morphologically confirmed myelodysplastic syndromes (MDS)

  • Refractory anemia (RA)
  • RA with ringed sideroblasts
  • RA with excess blasts
• Low, intermediate-1, or intermediate-2 risk by International Prognostic Scoring System criteria
• MDS secondary to prior chemotherapy and/or radiotherapy for other malignant disorders allowed
• Must have received prior transfusions of at least 4 units of red blood cells for anemia within the past 60 days
• Must be concurrently registered on SWOG-S9910 and SWOG-9007
• Ineligible for or refused participation in SWOG-S9920 (HLA-identical sibling peripheral blood stem cell transplantation)

PATIENT CHARACTERISTICS:

Age:

• 15 and over

Performance status:

• Zubrod 0-2

Life expectancy:

• Not specified

Hematopoietic:

• Not specified

Hepatic:

• Not specified

Renal:

• Not specified

Other:

• No other malignancy within the past 2 years except adequately treated basal cell or squamous cell skin cancer, carcinoma in situ of the cervix, or adequately treated stage I or II cancer in complete remission
• HIV negative
• Not pregnant or nursing
• Fertile patients must use effective contraception

PRIOR CONCURRENT THERAPY:

Biologic therapy:

• See Disease Characteristics
• Prior cytokines (e.g., interferon or interleukin), colony-stimulating factors, or epoetin alfa allowed
• No prior bone marrow or stem cell transplantation
• No concurrent growth factors (including epoetin alfa) except filgrastim (G-CSF) or sargramostim (GM-CSF) for neutropenia

Chemotherapy:

• See Disease Characteristics
• No prior remission induction chemotherapy for MDS
• Prior hydroxyurea allowed

Endocrine therapy:

• Not specified

Radiotherapy:

• See Disease Characteristics

Surgery:

• Not specified

Other:

• Prior amifostine allowed
• No calcium-channel blockers (diltiazem, nicardipine, or verapamil), antifungals (fluconazole, itraconazole, or ketoconazole), antibiotics (clarithromycin or erythromycin), or other drugs (bromocriptine or danazol) that would increase cyclosporine concentrations for 48 hours before, during, and for 48 hours after cyclosporine
• No antibiotics (nafcillin or rifampin) or anticonvulsants (carbamazepine, phenobarbital, or phenytoin) that would decrease cyclosporine concentrations for 14 days before and during cyclosporine