Study in Healthy Volunteers to Assess the Pharmacokinetics (PK) of Digoxin Administered Alone and in Combination With Vandetanib

Inclusion Criteria: * Provision of signed and dated, written informed consent prior to any study * specific procedures Volunteers must be males or females aged 18 to 45 years and with a weight of at least 50 kg and body mass index (BMI) between 18 and 30 kg/m2, * inclusive Females must have a negative pregnancy test at screening and on admission to the study center. Females must not be lactating and must be of non-childbearing potential defined as postmenopausal or documentation of irreversible surgical sterilization. Exclusion Criteria: * History of any clinically significant disease or disorder such as gastrointestinal, hepatic, renal or skin disease. * History of severe allergy/hypersensitivity or ongoing allergy/hypersensitivity, * Volunteers who are current smokers and have smoked or used nicotine products within the previous 6 months * Screening blood pressure of greater than 140/90 mmHg and/or a resting heart rate of less than 45 beats per minute (repeat test allowed at the Investigator's discretion * Clinically significant abnormal12-lead ECG as assessed by the Investigator, QTcF interval greater than 450 ms * Any positive result on screening for serum hepatitis B surface antigen, hepatitis C antibody, and human immunodeficiency virus (HIV), or positive screen for drugs of abuse.