A First Time In Human Study to Evaluate the Safety, Tolerability and Pharmacokinetics of GSK1399686

Inclusion criteria: * Healthy as determined by a responsible physician * Male, or only for the RDF cohort female of non-childbearing potential, between 18 and 65 years of age. * Body weight greater than 50 kg (110 lbs) and BMI within the range 18.5-29.9 kg/m2 (inclusive). * QTcB or QTcF \< 450 msec * Capable of giving written informed consent Exclusion criteria: * The subject has a positive pre-study drug/alcohol screen * History of regular alcohol consumption within 6 months of the study defined as an average weekly intake of greater than 21 units * Urinary cotinine levels indicative of active smoking or regular use of tobacco * A positive pre-study Hepatitis B surface antigen or positive Hepatitis C antibody * A positive test for HIV antibody * The subject has participated in a clinical trial and has received an investigational product within 30 days, 5 half-lives of the investigational product * Exposure to more than four new chemical entities within 12 months * Use of prescription or non-prescription drugs, including vitamins, herbal and dietary supplements (including St John's Wort) within 7 days * Consumption of red wine, seville oranges, grapefruit or grapefruit juice and/or pummelos, exotic citrus fruits, grapefruit hybrids or fruit juices within 7 days * Subject is receiving hormone replacement therapy * History of sensitivity to any of the study medications * History of sensitivity to heparin or heparin-induced thrombocytopenia