DISEASE CHARACTERISTICS:

• Histologically confirmed CD33+ acute myeloid leukemia (AML)

  • In first relapse from chemotherapy
  • Complete response lasting at least 3 months before relapse
• No CNS leukemia
• No secondary leukemia or history of antecedent hematologic disorder prior to initial onset of AML (e.g., myelodysplasia)

PATIENT CHARACTERISTICS:

Age:

• 60 and over

Performance status:

• ECOG 0-2

Life expectancy:

• Not specified

Hematopoietic:

• WBC less than 30,000/mm^3
• No bleeding or coagulation disorder except disease-related disseminated intravascular coagulation

Hepatic:

• Bilirubin no greater than 1.5 mg/dL
• PT and PTT no greater than 1.5 times upper limit of normal OR
• INR no greater than 1.3
• No history of chronic hepatitis or cirrhosis

Renal:

• Creatinine no greater than 2.0 mg/dL

Cardiovascular:

• No uncontrolled congestive heart failure
• No New York Heart Association class III or IV heart disease

Pulmonary:

• No severe pulmonary disease

Other:

• HIV negative
• No other concurrent medical disease that would preclude study entry
• No known hypersensitivity to phosphorothioate-containing oligonucleotides, gemtuzumab ozogamicin or any of its components, E. coli protein, or any product produced in E. coli
• No other concurrent malignancy
• No known human anti-human antibodies
• No uncontrolled seizure disorder
• No active uncontrolled infection
• Not pregnant or nursing
• Negative pregnancy test
• Fertile patients must use effective contraception

PRIOR CONCURRENT THERAPY:

Biologic therapy:

• No prior allogeneic or autologous stem cell transplantation
• No prior therapy with an anti-CD33 antibody (e.g., gemtuzumab ozogamicin or M195)

Chemotherapy:

• See Disease Characteristics
• At least 2 weeks since prior cancer chemotherapy except intrathecal chemotherapy or hydroxyurea

Endocrine therapy:

• Not specified

Radiotherapy:

• At least 2 weeks since prior systemic radiotherapy

Surgery:

• At least 2 weeks since prior major surgery
• No prior organ allograft

Other:

• At least 3 weeks since prior antileukemic therapy and recovered
• No other concurrent investigational therapy
• No concurrent immunosuppressive therapy