Inclusion Criteria

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