15. Subjects who have used prescription drugs within 2 weeks of first dosing. For Part B, patients are allowed; monotherapy with sulphonylureas, or metformin. In addition patients in Part B are allowed to take hypolipidaemic and/or antihypertensive treatments, provided that the doses have not been altered within the 4 weeks prior to entering the study. Other medications may be allowed if the Investigator and Sponsor both agree that they will not affect the outcome of the study or the safety of the subject.