13. Women of childbearing potential must have a negative serum or urine pregnancy test and not be breastfeeding prior to study therapy. Women of childbearing potential must be using an adequate form of contraception to avoid pregnancy during therapy and for at least 4 weeks after the end of study therapy in such a manner that the risk of pregnancy is minimized (Women of childbearing potential defined as not post-menopausal for 12 months or no previous surgical sterilization)