RATIONALE: Sorafenib may stop the growth of tumor cells by blocking some of the enzymes needed for cell growth and by blocking blood flow to the tumor.

PURPOSE: This phase II trial is studying the side effects and best dose of sorafenib and to see how well it works in treating patients with advanced malignant solid tumors.

OBJECTIVES:

Primary

• To evaluate the feasibility of re-escalating the dose of sorafenib tosylate in patients with advanced malignant solid tumors who initially required a dose reduction for toxicity, and dose escalation in those patients who are able to tolerate the initial dose.

Secondary

• To evaluate the efficacy of this drug in these patients who are able to tolerate a dose escalation initially or after a dose reduction compared to those who are unable to tolerate a dose escalation.

Tertiary

• To evaluate the percentage and demographic characteristics of patients who are able to tolerate 2 dose escalations without a dose reduction.

OUTLINE: This is a dose-finding study.

• Course 1: Patients receive oral sorafenib tosylate twice daily at dose level 0 on weeks 1-4.
• Course 2: Patients experiencing no dose-limiting or intolerable toxicities receive oral sorafenib tosylate at dose level +1 twice daily on weeks 5-8; while patients experiencing dose-limiting or intolerable toxicities receive oral sorafenib tosylate at dose level -1 once daily on weeks 5-8.
• Course 3: Depending on whether or not patients are experiencing dose-limiting or intolerable toxicities, they are escalated to dose level 0 or dose level +2 (patients in both dose levels receive oral sorafenib tosylate twice daily) in weeks 9-12, or de-escalated to dose level 0 or dose level -2 (patients in dose level -2 receives oral sorafenib tosylate once every other day) in weeks 9-12.
• Maintenance therapy: Patients receive oral sorafenib tosylate at the dose level* attained at the end of course 3. Treatment continues in the absence of unacceptable toxicity.
• Dose level de-escalation for toxicity or dose re-escalation after a toxicity-related dose reduction allowed to a maximum level of the initial dose level of the maintenance therapy.

After completion of study therapy, patients are followed for up to 1 year.

Inclusion Criteria

• Histologically or cytologically confirmed metastatic or unresectable solid tumor for which standard curative or palliative measures do not exist or are no longer effective or solid tumor for which sorafenib is considered acceptable therapy
• Age > 18 years old
• Performance Status 0 - 2
• Measurable or non-measurable disease.
• Adequate bone marrow, liver and renal function
• Any number of prior chemotherapy regimens are allowed.
• Any prior chemotherapy, immunotherapy or targeted therapy must have been completed at least 2 weeks prior to start of this protocol and all side effects resolved to grade 1 or less. Any prior radiation must have been completed at least 2 weeks prior to start of therapy.
• Women of childbearing potential must have a negative pregnancy test performed within 7 days prior to the start of treatment
• Women of childbearing potential and men must agree to use adequate contraception prior to study entry and for the duration of study participation. Men should use adequate birth control for at least three months after the last administration of sorafenib.
• Ability to understand and the willingness to sign a written informed consent.
• International normalized ratio < 1.5 or a Prothrombin Time/Partial thromboplastin time within normal limits.

Exclusion Criteria

• Prior therapy with sorafenib or sunitinib.
• Cardiac disease: Congestive heart failure > class II New York Heart Association.
• Symptomatic or uncontrolled brain metastasis.
• No component of squamous carcinoma can be present in any patient with non-small cell lung cancer
• Cardiac ventricular arrhythmias requiring anti-arrhythmic therapy.
• Uncontrolled hypertension defined as systolic blood pressure > 150 mmHg or diastolic pressure > 90 mmHg, despite optimal medical management.
• Known HIV infection or chronic Hepatitis B or C.
• Active clinically serious infection > CTCAE Grade 2.
• Thrombolic or embolic events such as a cerebrovascular accident including transient ischemic attacks within the past 6 months.
• Pulmonary hemorrhage/bleeding event > CTCAE Grade 2 within 4 weeks of first dose of study drug.
• Any other hemorrhage/bleeding event > CTCAE Grade 3 within 4 weeks of first dose of study drug.
• Serious non-healing wound, ulcer, or bone fracture.
• Evidence or history of bleeding diathesis or coagulopathy
• Major surgery, open biopsy or significant traumatic injury within 4 weeks of first dose of study drug.
• Use of St. John's Wort or rifampin
• Known or suspected allergy to sorafenib or any agent given in the course of this trial.
• Any condition that impairs patient's ability to swallow whole pills.
• Any significant malabsorption problem.
• Therapy with bevacizumab < 3 months prior to first dose of study drug.

With a sample size of 51 patients, this study has 90% power with an alpha of 0.05 to detect a dose re-escalation/escalation rate difference of 50% vs. 70%. If 31 or more patients are able to re-escalate successfully, the approach will be considered for further study.

Up to 2 years