DISEASE CHARACTERISTICS:

• Histologically confirmed acute lymphoblastic leukemia (ALL) or non-Hodgkin's lymphoma (including lymphoblastic lymphoma, Burkitt's lymphoma, and large cell lymphoma)

  • Not amenable to available curative therapies
• Relapsed or refractory disease after at least 1 standard chemotherapy and 1 salvage regimen

• CD22 positive according to at least 1 of the following criteria:

  • More than 15% CD22-positive malignant cells by immunohistochemistry
  • More than 30% CD22-positive malignant cells by fluorescent-activated cell sorter analysis
• Measurable or evaluable disease
• Prior CNS involvement allowed provided there is no current evidence of CNS malignancy

• No CNS leukemia or lymphoma as manifested by any of the following:

  • Cerebrospinal fluid (CSF) WBC ≥ 5/mm^3 and confirmation of CSF blasts
  • Cranial neuropathies secondary to underlying malignancy
  • Radiologically detected CNS lymphoma
• No isolated testicular ALL
• Ineligible for or refused hematopoietic stem cell transplantation OR has disease activity that prohibits the time required to identify a suitable stem cell donor

PATIENT CHARACTERISTICS:

Age

• 6 months to 24 years

Performance status

• ECOG 0-3 (12 to 24 years of age)
• Lansky 40-100% (under 12 years of age)

Life expectancy

• Not specified

Hematopoietic

• See Disease Characteristics
• Absolute neutrophil count > 1,000/mm^3 *
• Platelet count > 50,000/mm^3 * NOTE: *Non-leukemic patients only

Hepatic

• Bilirubin ≤ 2.0 mg/dL
• AST and ALT ≤ 5 times upper limit of normal
• No active hepatitis B or C infection

Renal

• Creatinine normal for age OR
• Creatinine clearance ≥ 60 mL/min

Immunologic

• No serum neutralization of more than 75% of the activity of 1 µg/mL of study drug
• HIV negative

Other

• Not pregnant or nursing
• Negative pregnancy test
• Fertile patients must use effective contraception
• No clinically significant unrelated systemic illness that would preclude study participation
• No other significant organ dysfunction that would preclude study participation
• No psychiatric illness or social situation that would preclude study compliance

PRIOR CONCURRENT THERAPY:

Biologic therapy

• See Disease Characteristics
• At least 1 week since prior colony-stimulating factors (e.g., filgrastim [G-CSF], sargramostim [GM-CSF], or epoetin alfa)
• Prior autologous or allogeneic hematopoietic stem cell transplantation (HSCT) allowed
• More than 100 days since prior allogeneic HSCT

Chemotherapy

• See Disease Characteristics
• At least 2 weeks since prior chemotherapy (6 weeks for nitrosoureas)

Endocrine therapy

• Concurrent corticosteroids allowed provided there has been no increase in the dose 1 week prior to and after study entry

  • Steroid taper allowed

Radiotherapy

• At least 3 weeks since prior radiotherapy

  • Allowed in the past 3 weeks provided the volume of the bone marrow treated is < 10% AND the patients has measurable disease outside of the radiation port

Surgery

• Not specified

Other

• Recovered from prior therapy
• At least 30 days since prior investigational drugs
• No other concurrent investigational drugs