An Open-Label, Multicenter, Phase II Study of Oral Lapatinib (GW572016) as Single Agent, Second-Line Therapy in Subjects With Metastatic Colorectal Cancer Who Have Progressed on First-Line Therapy With 5-Fluorouracil in Combination With Irinotecan or Oxaliplatin

Inclusion Criteria:

- Provide signed informed consent.

- Refractory Stage IV metastatic colorectal cancer.

- Received at least 2 cycles of first-line therapy with intravenous 5-FU
(5-fluorouracil) in combination with CPT-11 (irinotecan) and/or oxaliplatin.

- No more than one prior therapy.

- Tumor tissue available for testing.

- 4 weeks since first-line cancer regimen.

- Able to swallow and retain oral medication.

- Cardiac ejection fraction within the institutional range of normal as measured by
MUGA (Multiple Gated Acquisition Scan).

- Adequate kidney and liver function.

- Adequate bone marrow function.

Exclusion Criteria:

- Pregnant or lactating female.

- Conditions that would affect absorption of an oral drug

- First-line regimen did not include 5-fluorouracil with irinotecan and/or oxaliplatin.

- Serious medical or psychiatric disorder that would interfere with the patient''s
safety or informed consent.

- Severe cardiovascular disease or cardiac (heart) disease requiring a device.

- Active infection.

- Brain metastases.

- Concurrent cancer therapy or investigational therapy.

- Use of oral or intravenous steroids.

- Unresolved or unstable, serious toxicity from prior therapy.

- Prior therapy with an EGFR (Endothelial Growth Factor Receptor) and/or erbB-2
inhibitor.