RATIONALE: Sorafenib may stop the growth of tumor cells by blocking some of the enzymes needed for cell growth. Interferon alfa-2b may interfere with the growth of tumor cells. Sorafenib and interferon alfa-2b may also block blood flow to the tumor. Giving sorafenib together with interferon alfa-2b may kill more tumor cells.

PURPOSE: This randomized phase II trial is studying sorafenib and interferon alfa-2b to see how well they work compared to sorafenib alone in treating patients with metastatic kidney cancer.

OBJECTIVES:

Primary

• Compare the efficacy of sorafenib with vs without low-dose interferon alfa-2b, in terms of response rate, in patients with metastatic renal cell carcinoma.
• Compare the toxic effects of these regimens in these patients.

Secondary

• Compare the progression-free and overall survival of patients treated with these regimens.
• Compare the duration of response in patients treated with these regimens.

OUTLINE: This is a randomized study. Patients are stratified according to ECOG performance status (0 vs 1), presence of anemia (no vs hemoglobin < 14 g/dL for males OR hemoglobin < 12 g/dL for females), prior nephrectomy (no vs yes), and lactic dehydrogenase (LDH) level (LDH ≤ 1.5 times upper limit of normal (ULN) vs LDH > 1.5 times ULN). Patients are randomized to 1 of 2 treatment arms.

• Arm I: Patients receive oral sorafenib twice daily and low-dose interferon alfa-2b subcutaneously twice daily on days 1-28.
• Arm II: Patients receive sorafenib as in arm I. In both arms, courses repeat every 28 days in the absence of progressive disease or unacceptable toxicity.

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

PROJECTED ACCRUAL: A total of 80 patients (40 per treatment arm) will be accrued for this study.

DISEASE CHARACTERISTICS:

• Histologically and cytologically confirmed renal cell carcinoma
• Clear cell histology
• Metastatic disease
• Measurable disease, defined as ≥ 1 unidimensionally measurable lesion ≥ 20 mm by conventional techniques OR ≥ 10 mm by spiral CT scan
• No primary brain tumor, brain metastases, or leptomeningeal disease

PATIENT CHARACTERISTICS:

Age

• 18 and over

Performance status

• ECOG 0-1

Life expectancy

• Not specified

Hematopoietic

• Absolute neutrophil count ≥ 1,500/mm^3
• Platelet count ≥ 100,000/mm^3
• Hemoglobin > 9.0 g/dL (transfusion or epoetin alfa [e.g., Epogen^®] support allowed)
• No bleeding diathesis

Hepatic

• Bilirubin ≤ 2.0 mg/dL
• AST and/or ALT ≤ 2.5 times upper limit of normal (ULN) (5 times ULN if due to liver metastases)
• Albumin > 3.0 g/dL

Renal

• Creatinine ≤ 2.0 mg/dL

Cardiovascular

• Must not have any of the following cardiovascular conditions:
• Uncontrolled hypertension
• History of stroke
• Clinically significant cardiovascular disease
• History of myocardial infarction
• Unstable angina
• New York Heart Association class II-IV congestive heart failure
• Serious cardiac dysrhythmia requiring medication
• Peripheral vascular disease ≥ grade 2

Other

• Not pregnant or nursing
• Negative pregnancy test
• Fertile patients must use effective contraception
• Able to swallow pills
• No other malignancy within the past 5 years except nonmelanoma skin cancer or carcinoma in situ of any site
• No active acute infection
• No history of disease, metabolic dysfunction, physical examination finding, or clinical laboratory finding that would preclude study participation
• No uncontrolled seizure disorder
• No history of severe depression

PRIOR CONCURRENT THERAPY:

Biologic therapy

• Not specified

Chemotherapy

• Not specified

Endocrine therapy

• Not specified

Radiotherapy

• No prior radiotherapy

Surgery

• Not specified

Other

• No prior systemic anticancer therapy
• No other concurrent experimental drugs
• No concurrent combination antiretroviral therapy for HIV-positive patients
• No concurrent rifampin or Hypericum perforatum (St. John''''s wort)
• No concurrent cytochrome p450 enzyme-inducing antiepileptic drugs (e.g., phenytoin, carbamazepine, or phenobarbital)
• No concurrent therapeutic anticoagulation therapy
• Concurrent prophylactic anticoagulation (i.e., low-dose warfarin) of venous access devices allowed provided requirements for PT, PTT, and INR are met
• Concurrent bisphosphonates allowed