Investigator Decision

RATIONALE: Human T-cell lymphotropic virus type 1 (HTLV-1) can cause cancer. Zidovudine is an antiviral drug that acts against the human T-cell lymphotropic virus type 1. Giving zidovudine, interferon alfa-2b, and PEG-interferon alfa-2b together may stimulate the immune system and slow down or keep the cancer cell from growing.

PURPOSE: This clinical trial is studying how well giving zidovudine together with interferon alfa-2b and PEG-interferon alfa-2b works in treating patients with human T-cell lymphotropic virus type 1-associated adult T-cell leukemia/lymphoma.

OUTLINE: This is a multicenter study.

• Induction therapy: Patients receive zidovudine IV twice daily on days 1-14, and recombinant interferon alfa-2b IV twice daily on days 3-14. Patients achieving clinical complete response (CR) proceed to part 1 maintenance therapy; patients achieving partial response (PR) receive another 7 days of zidovudine and recombinant interferon alfa-2b and then proceed to part 1 maintenance therapy.

• Part 1 maintenance therapy: Patients receive oral zidovudine twice daily and PEG-interferon alfa-2b subcutaneously (SC) once weekly, beginning on day 14 or 21 and continue to day 60. Patients are evaluated after completion of part 1 maintenance therapy and proceed to part 2 maintenance therapy.

• Part 2 maintenance therapy: Patients achieving CR with undetectable clonal disease proceed to group A; patients achieving CR with minimal residual disease (by PCR) or PR proceed to group B.

  • Group A: Patients receive oral zidovudine twice daily and PEG-interferon alfa-2b SC once weekly. Treatment continues in the absence of disease progression or unacceptable toxicity.
  • Group B: Patients receive oral zidovudine twice daily and PEG-interferon alfa-2b SC once weekly for 12 weeks and undergo reevaluation. Patients in continued CR with minimal residual disease or stable PR receive oral valproic acid twice daily, PEG-interferon alfa-2b SC once weekly, and oral zidovudine twice daily for 6 months. At that point (month 9) patients with no detectable clonal disease continue their previous treatment, while patients with minimal residual disease receive PEG-interferon alfa-2b SC and oral zidovudine twice daily in the absence of disease progression or unacceptable toxicity.

Blood samples are collected at baseline, days 1 and 2, and months 3, 6, and 12 for protein, genomic DNA, and RNA analysis. Baseline molecular characteristics of the tumor and tumor response to treatment is assessed.

After completion of study treatment, patients are followed every 3 months for 1 year.

Inclusion Criteria

• Any stage, histologically or cytological documented adult T-cell leukemia/lymphoma (ATLL), leukemic types only (smoldering, chronic or acute). See Appendix I for definitions of the clinical subtypes.

• Patients who have received prior treatment, including zidovudine and/or IFN, are eligible, provided that zidovudine/IFN therapy did not result in progressive disease.

• Documented HTLV-I infection: documentation may be serologic assay (ELISA, Western blot) and confirmed to be HTLV-I rather than HTLV-2 by differential Western blot (e.g., Genelabs Diagnostics HTLV Blot 2.4) or PCR.

• Measurable or evaluable disease.

• Age 18 or older.

• Karnofsky performance status ≥ 50%.

• Patients must have adequate end organ and bone marrow function as defined below:

  • Absolute neutrophil count ≥ 1,000 cells/mm3 and platelets ≥ 50,000 cells/mm3 unless cytopenias are secondary to ATLL.
  • Adequate hepatic function: (transaminase ≤ 7 times the upper limit of normal, total bilirubin < 2.0), unless secondary to hepatic infiltration with lymphoma. If the elevated bilirubin is felt to be secondary to Indinavir or Atazavinir therapy (anti-HIV medications), patients will be allowed to enroll on protocol if the total bilirubin is ≤ 3.5 mg/dl provided that the direct bilirubin is normal.
  • Creatinine < 2.0 unless due to lymphomatous infiltration.

• Patients who are HIV+ are also eligible.

• Females with childbearing potential must have a negative serum pregnancy test within 72 hours of entering into the study. Males and females must agree to use adequate birth control if conception is possible during the study. Women must avoid pregnancy and men avoid fathering children while in the study.

• Able to give consent.

• Patients already receiving erythropoietin or granulocyte-colony stimulating factor (G-CSF) are eligible.

Exclusion Criteria

• Concurrent active malignancies, with the exception of in situ carcinoma of the cervix, non-metastatic, non-melanomatous skin cancer, or Kaposi's sarcoma not requiring systemic chemotherapy.
• Grade 3 or 4 cardiac failure and/or ejection fraction < 50%.
• Psychological, familial, sociological or geographical conditions that do not permit treatment and/or medical follow-up required to comply with the study protocol.
• Patients may not be receiving any other investigational agents.
• Uncontrolled intercurrent illness including, but not limited to, ongoing or active infection, symptomatic congestive heart failure, unstable angina pectoris, cardiac arrhythmia, or psychiatric illness/social situations that would limit compliance with study requirements.
• Pregnant or breast-feeding women.
• Hypersensitivity to interferon alpha-2b, peginterferon alpha-2b, zidovudine or any component of the formulation
• Autoimmune or viral hepatitis or decompensated liver disease unless due to lymphoma.