GSK557296 is being studied in women for the indication of enhanced embryo and or blastocyst implantation in women undergoing IVF treatment. This study will be the first dosing experience with this compound in women. It is important to characterize the pharmacokinetics of GSK557296 in women to determine the most appropriate doses and dosing regimens for future clinical studies. Understanding the pharmacokinetics of GSK557296 in women will also enable more accurate characterization of any exposure-response relationship in future studies.

Two previous studies with GSK557296 were conducted in men with oral doses ranging from 10 milligram (mg) to 200 mg. GSK557296 is being studied in women for the indication of enhanced embryo and or blastocyst implantation in women undergoing IVF treatment. This is a bridging study to characterize the pharmacokinetics of GSK557296 in women to determine the most appropriate doses and dosing regimens for future clinical studies.

This is a non-randomized, open label, adaptive design study in healthy female volunteers. A maximum total of 48 subjects, will participate in different cohorts. Subjects in Cohort 1 will receive 10 mg single dose followed by repeat dose. A one week break will occur to allow for analysis of the PK data, prior to starting the second Cohort. Subjects in Cohort 2 will receive 150 mg single dose followed by repeat dose. Cohort 3 and Cohort 4 were adaptive based on the requirement of additional doses to be studies after PK data will be analyzed from each of the first 2 cohorts.

Inclusion Criteria:

• Alanine aminotransferase (ALT), alkaline phosphatase and bilirubin <=1.5xupper limit of normal (ULN)
• Single or QTcF < 450 millisecond (msec); or QTc < 480 msec in subjects with Bundle Branch Block
• Healthy as determined by a responsible and experienced physician
• Female between 18 and 45 years of age inclusive, at the time of signing the informed consent
• A female subject is eligible to participate if she is of Child-bearing potential and is abstinent or agrees to use contraception methods to sufficiently minimize the risk of pregnancy during the study.
• Body weight >= 50 kilogram (kg) and Body Mass Index (BMI) within the range 19 to 29.9 kg per meter^2 (inclusive)

Exclusion Criteria:

• A positive pre-study Hepatitis B surface antigen or positive Hepatitis C antibody result at screening or within 3 months of screening
• Current or chronic history of liver disease, or known hepatic or biliary abnormalities (with the exception of Gilbert's syndrome or asymptomatic gallstones)
• A positive pre-study drug or alcohol screen
• A positive test for HIV antibody
• History of regular alcohol consumption within 6 months of the study
• The subject has participated in a clinical trial and has received an investigational product within the following time period prior to the first dosing day in the current study: 30 days, 5 half-lives or twice the duration of the biological effect of the investigational product (whichever is longer), exposure to more than four new chemical entities within 12 months prior to the first dosing day Unable to refrain from the use of prescription or non-prescription drugs, with the exception of Oral contraceptives, within 7 days or 5 half-lives (whichever is longer) prior to the first dose of study medication history of sensitivity to any of the study medications, or components thereof or a history of drug or other allergy that, in the opinion of the investigator or GSK Medical Monitor, contraindicates their participation
• Where participation in the study would result in donation of blood or blood products in excess of 500 milliliter (mL) within a 56 day period
• Pregnant females
• Lactating females
• Unwillingness or inability to follow the procedures outlined in the protocol
• Subject is mentally or legally incapacitated
• Urinary cotinine levels indicative of smoking or history or regular use of tobacco- or nicotine-containing products within 6 months prior to screening
• Unable to refrain from consumption of red wine, seville oranges, grapefruit or grapefruit juice and/or pomelos, exotic citrus fruits, grapefruit hybrids or fruit juices from 7 days prior to the first dose of study medication

Patient-level data for this study will be made available through www.clinicalstudydatarequest.com following the timelines and process described on this site.