RATIONALE: Monoclonal antibodies, such as anti-IL-6 chimeric monoclonal antibody, can block tumor growth in different ways. Some block the ability of tumor cells to grow and spread. Others find tumor cells and help kill them or carry tumor-killing substances to them.

PURPOSE: This phase II trial is studying how well anti-IL-6 chimeric monoclonal antibody works in treating patients with metastatic prostate cancer that did not respond to hormone therapy.

OBJECTIVES:

Primary

• Assess the confirmed prostate-specific antigen response in patients with hormone-refractory metastatic prostate cancer treated with anti-IL-6 chimeric monoclonal antibody.

Secondary

• Assess overall survival and progression-free survival of these patients.
• Assess the objective response rate (confirmed and unconfirmed, complete and partial response) in patients with measurable disease treated with this regimen.
• Assess the qualitative and quantitative toxicities of this regimen.

OUTLINE: This is an open-label, multicenter study.

Patients receive anti-IL-6 chimeric monoclonal antibody IV over 2 hours on day 1. Treatment repeats every 2 weeks for up to 12 courses in the absence of disease progression or unacceptable toxicity.

After completion of study treatment, patients are followed every 3 months for 1 year and then every 6 months for up to 2 years.

PROJECTED ACCRUAL: A total of 40 patients will be accrued for this study.

DISEASE CHARACTERISTICS:

• Histologically confirmed adenocarcinoma of the prostate

  • Metastatic disease (N1 and/or M1)

• Disease unresponsive or refractory to androgen-deprivation therapy

• Must have received only 1 prior chemotherapy regimen comprising a taxane OR mitoxantrone

• Disease progression as defined by one or more of the following:

  • Progression of measurable disease

    • Prior radiotherapy allowed provided radiotherapy was completed ≥ 2 months ago and lesion progressed since radiotherapy

  • Progression of nonmeasurable disease

    • Prior radiotherapy within the past 2 months allowed, but disease is considered nonmeasurable

  • Rising prostate-specific antigen (PSA) after > 2 courses of chemotherapy OR within 6 months of last chemotherapy dose

    • Rising PSA defined as at least 2 consecutive rises in PSA to be documented over a reference value (measure 1)

• PSA ≥ 5 ng/mL

• Surgical or medical castration required

  • Castration using luteinizing hormone-releasing hormone agonist (leuprolide acetate or goserelin) or antagonist (abarelix) should not be interrupted

• No history of brain metastases OR currently treated or untreated brain metastases

  • Patients with clinical suspicion of brain metastases must have a brain CT scan or MRI negative for metastatic disease within the past 56 days

PATIENT CHARACTERISTICS:

• Zubrod performance status 0-2

• Fertile patients must use effective contraception

• Absolute granulocyte count ≥ 1,500/mm³ (transfusion independent)

• Platelet count ≥ 100,000/mm³ (transfusion independent)

• Hemoglobin ≥ 9 g/dL (transfusion independent)

• Creatinine clearance ≥ 40 mL/min

• Bilirubin ≤ 2 times upper limit of normal (ULN)

• Aspartate aminotransferase (AST) ≤ 2 times ULN

• No uncontrolled intercurrent illnesses including, but not limited to, the following:

  • Diabetes mellitus
  • Ongoing or active infection
  • Symptomatic congestive heart failure
  • Unstable angina pectoris
  • Cardiac arrhythmia

• No psychiatric illness or social situation that would preclude study compliance

• No known HIV positivity

• No other prior malignancy except for the following:

  • Adequately treated basal cell or squamous cell skin cancer
  • Adequately treated stage I or II cancer in complete remission
  • Any other cancer from which the patient has been disease-free for 5 years

PRIOR CONCURRENT THERAPY:

• See Disease Characteristics

• At least 21 days since prior surgery and recovered

• At least 28 days since prior chemotherapy and recovered

• At least 28 days since prior flutamide or ketoconazole

• At least 28 days since prior radiotherapy (to < 30% of the bone marrow only) and recovered

  • Prior samarium Sm 153 lexidronam pentasodium allowed
  • No prior strontium chloride Sr 89

• At least 42 days since prior bicalutamide or nilutamide

• More than 60 days since prior murine or chimeric proteins or human/murine monoclonal antibody

• Concurrent bisphosphonate therapy allowed provided the following are true:

  • Therapy commenced at least 3 weeks ago
  • Therapy continues for the entire duration of study treatment

• No other concurrent anticancer therapy, including cytotoxic therapy, biologic therapy, radiotherapy, or hormonal therapy (except for luteinizing hormone-releasing hormone agonist or antagonist in patients who have not had an orchiectomy)