A Phase I Study to Test Alternate Oral Formulations vs the Current Tablet Formulation of Lapatinib

Inclusion Criteria: * The subject is healthy as defined per protocol. * The subject is male or female. * A female is eligible to enter and participate in this study if she is of: * Non-childbearing potential (i.e., physiologically incapable of becoming pregnant), including any female who: * Has had a documented (medical report verification) hysterectomy or double oophorectomy or * Is 6 weeks postsurgical bilateral oophorectomy with or without hysterectomy or * Is post-menopausal (defined as females older than 45 years of age with 12 months of spontaneous amenorrhea or 6 months of spontaneous amenorrhea with serum FSH levels higher than 40 mIU/ml) * Childbearing potential, has a negative serum pregnancy test at Screening, and agrees to one of the following : * Complete abstinence from sexual intercourse from two weeks prior to administration of the study drug and throughout the study, and through the follow-up visit which will occur within 10 to 14 days after completion of the last treatment. * Vasectomized partner * Intrauterine device (IUD) with a documented failure rate of less than 1% per year. * Double-barrier contraception (condom with spermicidal jelly, foam suppository, or film; diaphragm with spermicide; or male condom and diaphragm). * Hormonal contraceptive plus male condom. * Age: 18 to 60 years inclusive. * BMI within the range 19 to 31.0 kg/m2. * Able to swallow and retain oral medication. * The subject is willing to refrain from the use of illicit drugs and adhere to other protocol-stated restrictions while participating in the study. * The subject is able to understand and comply with protocol requirements and instructions and is likely to complete the study as planned. * A signed and dated written informed consent is obtained from the subject or the subject's legally acceptable representative prior to screening. Exclusion Criteria: * As a result of the medical interview, physical examination or screening investigations, the Principal Investigator considers the subject unfit for the study. * The subject meets ECG-related exclusion criteria listed in the protocol or has serum magnesium or potassium below the normal range at screening. * The subject has a history of drug or other allergy, which, in the opinion of the Principal Investigator, contraindicates participation. * The subject has a known immediate or delayed hypersensitivity reaction or idiosyncrasy to drugs chemically related to the study drug, including but not limited to Tarceva (erlotinib) or Iressa (gefitinib). * The subject has a history of sensitivity to heparin or heparin-induced thrombocytopenia (applicable if heparin is used during pharmacokinetic sampling). * The subject participated in a study with a new molecular entity or any other trial during the previous 30 days. * The subject donated blood in excess of 500 mL within 56 days prior to dosing or intends to donate in the month after completing the study. * Use of prescription or non-prescription drugs (including vitamins and herbal supplements) within two weeks prior to dosing or during the study, however, acetaminophen up to two grams per day is acceptable. * History of alcohol/drug abuse or dependence within 12 months of the study as per protocol. * The subject is a smoker or has smoked in the last four months. * The subject tested positive for hepatitis C antibody, hepatitis B surface antigen, or HIV antibody. * The subject has a positive urine test for drugs of abuse or is positive for alcohol use at pre-study screening. * Consumption of red wine, Seville oranges, grapefruit or grapefruit juice from 7 days prior to the first dose of study medication until collection of the final PK blood sample.