An Efficacy Study Comparing ZD6474 to Placebo in Medullary Thyroid Cancer

Inclusion Criteria

• Confirmed diagnosis of unresectable, locally advanced or metastatic hereditary or sporadic Medullary Thyroid Cancer.
• Presence of measurable tumor
• Able to swallow medication

Exclusion Criteria

• Major surgery within 4 weeks before randomization
• Last dose of prior chemotherapy received less than 4 weeks prior to randomization
• Radiation therapy within the last 4 weeks prior to randomization(with exception of palliative radiotherapy)
• Brain metastases or spinal cord compression, unless treated at least 4 weeks before first dose and stable without steroid treatment for 10 days
• Significant cardiac events
• Previous ZD6474 treatment