DISEASE CHARACTERISTICS:

• Histologically or cytologically confirmed nasopharyngeal carcinoma, meeting the following criteria:

  • WHO type II-III disease
  • Stage IV or recurrent disease
• Must have failed at least 1 prior line of chemotherapy for metastatic or recurrent disease
• Measurable disease, defined as ≥ 1 unidimensionally measurable lesion ≥ 20 mm by conventional techniques OR ≥ 10 mm by spiral CT scan
• No known brain metastases

PATIENT CHARACTERISTICS:

• ECOG performance status (PS) 0-2 or Karnofsky PS 70-100%
• Life expectancy > 3 months
• WBC ≥ 3,000/mm³
• Absolute neutrophil count ≥ 1,500/mm³
• Platelet count ≥ 100,000/mm³
• Bilirubin normal
• AST and ALT ≤ 2.5 times upper limit of normal (ULN)
• Creatinine normal OR creatinine clearance ≥ 60 mL/min
• Proteinuria ≤ 1+ on 2 consecutive dipsticks taken ≥ 1 week apart
• PT, INR, and PTT ≤ 1.2 times ULN

• Systolic blood pressure (BP) ≤ 140 mm Hg and diastolic BP ≤ 90 mm Hg

  • Initiation or adjustment of BP medication allowed provided the average of 3 BP readings are < 140/90 mm Hg prior to study entry
• No history of allergic reaction attributed to compounds of similar chemical or biological composition to pazopanib hydrochloride or to other study agents
• No abdominal fistula, gastrointestinal perforation, or intraabdominal abscess within the past 28 days
• No cerebrovascular accident within the past 6 months

• No history of any of the following diseases within the past 12 weeks:

  • Myocardial infarction
  • Cardiac arrhythmia
  • Admission for unstable angina
  • Cardiac angioplasty or stenting
  • Venous thrombosis

• No New York Heart Association (NYHA) class III-IV heart failure

  • Patients with a history of NYHA class II heart failure are eligible provided they are asymptomatic on treatment
• No significant ECG abnormalities, including QTc prolongation (i.e., QTc ≥ 500 msec)
• No serious or nonhealing wound, ulcer, or bone fracture

• No condition that would impair the ability to swallow and retain pazopanib hydrochloride, including any of the following:

  • Gastrointestinal tract disease resulting in an inability to take oral medication
  • Requirement for IV alimentation
  • Prior surgical procedures affecting absorption
  • Active peptic ulcer disease

• No concurrent uncontrolled illness including, but not limited to, the following:

  • Coagulopathy
  • Ongoing or active infection
  • Psychiatric illness or social situation that would preclude study compliance
• No known allergy to CT contrast agents
• Not pregnant or nursing
• Negative pregnancy test
• Fertile patients must use effective contraception

PRIOR CONCURRENT THERAPY:

• See Disease Characteristics
• More than 4 weeks since prior chemotherapy (6 weeks for nitrosoureas or mitomycin C) and recovered
• More than 4 weeks since prior radiotherapy
• At least 4 weeks since prior surgery
• No prior antiangiogenesis therapy
• No other concurrent investigational agents
• No other concurrent anticancer therapy
• No concurrent medications or substances known to affect or with the potential to affect the activity or pharmacokinetics of pazopanib hydrochloride, as determined by the Principal Investigator
• No concurrent medications that have the potential to interact with the cytochrome P450 isoenzymes CYP2C9 and CYP3A4

• No concurrent therapeutic warfarin

  • Low molecular weight heparin or prophylactic low-dose warfarin allowed
• No concurrent antiretroviral therapy for HIV-positive patients