• Response (complete remission [CR] or complete remission with incomplete recovery of platelet count [CRp]) rate after induction [ Designated as safety issue: No ]
• Disease-free survival after CR/CRp [ Designated as safety issue: No ]
• Incidence of relapse after CR/CRp [ Designated as safety issue: No ]
• Incidence of death without relapse after CR/CRp [ Designated as safety issue: No ]
• Event-free survival [ Designated as safety issue: No ]
• Toxicity (highest grade) assessed by International Working Group CTC v2.0 [ Designated as safety issue: Yes ]

• Response (complete remission [CR] or complete remission with incomplete recovery of platelet count [CRp]) rate after induction
• Disease-free survival after CR/CRp
• Incidence of relapse after CR/CRp
• Incidence of death without relapse after CR/CRp
• Event-free survival
• Toxicity (highest grade) assessed by International Working Group CTC v2.0

RATIONALE: Drugs used in chemotherapy use different ways to stop cancer cells from dividing so they stop growing or die. Monoclonal antibodies can locate cancer cells and either kill them or deliver cancer-killing substances to them without harming normal cells. It is not yet known if combining combination chemotherapy with monoclonal antibody therapy will kill more cancer cells.

PURPOSE: Randomized phase III trial to determine the effectiveness of combination chemotherapy with or without gemtuzumab ozogamicin in treating patients who have acute myeloid leukemia.

OBJECTIVES:

• Determine the antileukemic activity of standard induction chemotherapy with or without gemtuzumab ozogamicin in elderly patients with previously untreated acute myeloid leukemia.
• Determine the overall survival of patients treated with these regimens.
• Determine the rate of response, disease-free survival, event-free survival, incidence of relapse, and incidence of death of patients treated with these regimens.
• Determine the rate, type, and grade of toxicity of these regimens in these patients.

OUTLINE: This is a randomized, open-label, multicenter study. Patients are stratified according to age (61-69 vs 70-75), CD33 positivity (less than 5% vs 5-19% vs 20-80% vs more than 80% vs unknown), initial WBC before hydroxyurea administration if needed (less than 30,000/mm^3 vs at least 30,000/mm^3), and participating center. Patients are randomized to 1 of 2 treatment arms.

• Arm I:

  • Induction (phase I): Patients receive gemtuzumab ozogamicin IV over 2 hours on days 1 and 15.
  • Induction (phase II/MICE regimen): Beginning between days 50 and 53, patients receive mitoxantrone IV over 30 minutes on days 1, 3, and 5; etoposide IV over 1 hour on days 1-3; and cytarabine IV continuously on days 1-7. Bone marrow evaluation is performed on day 29. Patients with partial remission (PR) receive a second course of MICE chemotherapy regimen. Patients with complete remission (CR) after 1 or 2 courses of MICE regimen proceed to consolidation therapy. Patients with progressive disease go off therapy.
  • Consolidation: Beginning within 4 weeks of documentation of CR, patients receive gemtuzumab ozogamicin IV over 2 hours on day 0; idarubicin IV on days 1, 3, and 5; etoposide IV over 1 hour on days 1-3; and cytarabine IV continuously on days 1-5. After at least day 30, patients receive a second consolidation course in the absence of disease progression or unacceptable toxicity.

• Arm II:

  • Induction (MICE regimen): Patients receive mitoxantrone, etoposide, and cytarabine as in arm I induction. Bone marrow evaluation is performed on day 29. Patients with PR receive a second course of MICE chemotherapy regimen. Patients with CR after 1 or 2 courses of MICE regimen proceed to consolidation therapy. Patients with progressive disease go off therapy.
  • Consolidation: Patients receive idarubicin, etoposide, and cytarabine as in arm I consolidation.

Patients are followed monthly for 1 year, every 3 months for 2 years, and then every 6 months thereafter.

PROJECTED ACCRUAL: A total of 450 patients (225 per treatment arm) will be accrued for this study within 3.75 years.

• Drug: cytarabine
• Drug: etoposide
• Drug: gemtuzumab ozogamicin
• Drug: idarubicin
• Drug: mitoxantrone hydrochloride

DISEASE CHARACTERISTICS:

• Diagnosis of acute myeloid leukemia (AML)

  • Bone marrow blasts at least 20% by bone marrow aspiration or biopsy

  • FAB subtypes M0-M2 and M4-M7

    • No acute promyelocytic leukemia (FAB subtype M3)

• Previously untreated primary or secondary AML, including AML after myelodysplastic syndromes

  • Hydroxyurea and/or corticosteroid therapy for no more than 14 days allowed
• No blast crisis of chronic myelogenous leukemia
• No AML supervening after other myeloproliferative diseases
• No active CNS leukemia

PATIENT CHARACTERISTICS:

Age

• 61 to 75

Performance status

• WHO 0-2

Life expectancy

• Not specified

Hematopoietic

• WBC less than 30,000/mm^3 (pretreatment with hydroxyurea for no more than 14 days allowed)

Hepatic

• Bilirubin no greater than 3 times upper limit of normal (ULN)

Renal

• Creatinine no greater than 3 times ULN

Cardiovascular

• No concurrent severe cardiovascular disease
• No arrhythmias requiring chronic treatment
• No congestive heart failure
• No symptomatic ischemic heart disease

Pulmonary

• No severe pulmonary dysfunction (CTC grade 3-4)

Other

• HIV negative
• No other uncontrolled infection
• No other concurrent malignant disease
• No severe concurrent neurological or psychiatric disease
• No prior alcohol abuse
• No psychological, familial, sociological, or geographical condition that would preclude study participation

PRIOR CONCURRENT THERAPY:

Biologic therapy

• No concurrent hematopoietic growth factors (filgrastim [G-CSF] or sargramostim [GM-CSF]) except for life-threatening infection due to neutropenia

Chemotherapy

• See Disease Characteristics

Endocrine therapy

• See Disease Characteristics

Radiotherapy

• Not specified

Surgery

• Not specified

Other

• No prior enrollment in this trial