1. non-childbearing potential (i.e. physiologically incapable of becoming pregnant). This includes any female who is post-menopausal. For the purposes of this study, post menopausal is defined as being amenorrhoeic for greater than 2 years with an appropriate clinical profile, e.g. age appropriate, history of vasomotor symptoms. Postmenopausal status will be confirmed by serum FSH and oestradiol concentrations at screening. Surgical sterility will be defined as females who have had a hysterectomy and/or bilateral oophorectomy or tubal ligation. OR