RATIONALE: Antineoplastons are naturally-occurring substances that may also be made in the laboratory. Antineoplastons may inhibit the growth of cancer cells.

PURPOSE: This phase II trial studies the effectiveness of antineoplaston therapy in treating women who have stage IV breast cancer that has not responded to previous therapy.

OBJECTIVES:

• Determine the safety and possible effectiveness of antineoplastons A10 and AS2-1 in women with stage IV breast carcinoma.
• Describe the response to, tolerance to, and side effects of this regimen in these patients.

OUTLINE: Patients receive gradually escalating doses of antineoplaston A10 and antineoplaston AS2-1 by intravenous injection 6 times daily until the maximum tolerated dose is reached.

Treatment continues for at least 3 months in the absence of unacceptable toxicity or disease progression. Patients achieving complete response (CR) continue treatment for an additional 8 months after reaching CR.

Tumors are measured at least every 2 months for 1 year and then every 3 months for 1 year.

PROJECTED ACCRUAL: A total of 20-40 patients will be accrued for this study.

Ages Eligible for Study:  18 Years and above,  Genders Eligible for Study:  Both

Criteria

DISEASE CHARACTERISTICS:

• Histologically confirmed stage IV breast cancer that is unlikely to respond to existing therapy and for which no curative therapy exists
• Must have failed prior standard therapy
• Measurable disease by MRI or CT scan
• Tumor must be at least 2 cm in the lymph nodes in the head, neck, axillary, inguinal, or femoral areas and at least 0.5 cm in other locations
• Hormone receptor status:
• Not specified

PATIENT CHARACTERISTICS: Age:

• 18 and over

Sex:

• Female

Menopausal Status:

• Not specified

Performance status:

• Karnofsky 60-100%

Life expectancy:

• At least 2 months

Hematopoietic:

• WBC at least 2,000/mm^3
• Platelet count at least 50,000/mm^3

Hepatic:

• Bilirubin nor greater than 2.5 mg/dL
• SGOT/SGPT no greater than 5 times upper limit of normal
• No hepatic failure

Renal:

• Creatinine no greater than 2.5 mg/dL
• No history of renal conditions that contraindicate high dosages of sodium

Cardiovascular:

• No chronic heart failure
• No uncontrolled hypertension
• No history of congestive heart failure
• No history of other cardiovascular conditions that contraindicate high dosages of sodium

Pulmonary:

• No severe lung disease, such as chronic obstructive pulmonary disease

Other:

• Not pregnant or nursing
• Fertile patients must use effective contraception during and for 4 weeks after study participation
• No serious medical or psychiatric disorders
• No active infections
• No other serious concurrent disease

PRIOR CONCURRENT THERAPY: Biologic therapy:

• At least 4 weeks since prior immunotherapy, except in patients with disease progression during or after initial therapy
• Recovery from prior immunotherapy
• No concurrent immunomodulating agents

Chemotherapy:

• At least 4 weeks since prior chemotherapy (6 weeks for nitrosoureas), except in patients with disease progression during or after initial therapy
• Recovery from prior chemotherapy
• No concurrent antineoplastic agents

Endocrine therapy:

• At least 12 weeks since prior hormonal therapy, except in patients with disease progression during and after initial therapy
• Concurrent corticosteroids allowed
• Recovery from prior hormonal therapy

Radiotherapy:

• At least 8 weeks since prior radiotherapy and recovered (patients with multiple tumors who have received radiotherapy to some, but not all, tumors may be admitted earlier than 8 weeks)

Surgery:

• Recovered from any prior surgery

Other:

• No prior antineoplaston therapy
• Prior cytodifferentiating agent allowed