Study to determine if contacting patients with MTC more frequently results in earlier detection and treatment of signs and symptoms of AEs and thus a decrease in the percentage of time patients experience AEs during first 12 months on vandetanib treatment - 88

Exclusion Criteria

• - Unstable brain metastases or spinal cord compression that require treatment, unless treated at least 4 weeks before first dose and stable without steroid treatment for 10 days
• - Major surgery within 4 weeks before randomization
• - The last dose of prior chemotherapy received less than 3 weeks prior to randomization
• - Radiation therapy not completed prior to the first dose of vandetanib
• - Significant cardiac event, superior vena cava syndrome, NYHA classification of heart disease ≥2, within 12 weeks before randomization, or presence of cardiac disease that in the opinion of the Investigator increases risk of ventricular arrhythmia
• - Creatinine clearance <30 ml/min (calculated by Cockcroft-Gault formula),Patients with moderate renal impairment, defined as creatinine clearance ≥30 to <50 ml/min, must start vandetanib at a reduced dose of 200 mg