To Assess the Excretion Balance and Pharmacokinetics of a Single Oral Dose of [14C]GW856553 in Healthy Adult Males

• Clinical Safety data. PK parameters of GW856553 and drug-related material (radioactivity) in plasma urine and faeces following oral dosing. Samples are collected for approximately 10 days (or longer) following oral dosing. [ Time Frame: approximately 10 days ]
• AUC(0-inf), Cmax, AUC(0-t), tmax and t½ of total drug-related material (radioactivity) in plasma following oral dosing.
• AUC(0-inf), Cmax, AUC(0-t), tmax, t½ of GW856553 and its major metabolite GSK198602 in plasma following oral dosing.
• Adverse events, ECG, vital signs and clinical laboratory tests (including LFTs).
• Characterisation and quantification of metabolites in plasma, urine and faecal homogenates will be performed under a separate protocol by Drug Metabolism and Pharmacokinetics (DMPK), GSK and results will be reported in a separate report.

This will be an open label study conducted at one site. Six healthy male subjects will be enrolled to ensure at least four fully evaluable subjects. Each subject will receive a single 10 mg oral dose of GW856553 containing 50 microCi of [14C] GW856553. Urine and faecal samples will be collected until 216 h after dosing but subjects may be discharged after 168 h if 90% of the dose is recovered and/or <1% of the dose is excreted in a 24 h period. Blood and plasma will be collected at various sample times after dosing to measure parent drug and total drug-related material. Samples of urine, faeces and plasma will be transferred into a separate study to characterise and quantify metabolites in these matrices. Safety will be assessed by adverse event monitoring, vital signs, ECG and clinical laboratory tests.

Inclusion Criteria:

• Healthy male aged between 30 and 60 years inclusive, at the time of screening.
• Body weight >/ 50 kg (110 lbs).
• A body mass index (BMI) within the range of 18.5 to 29.9 kg/m2 inclusive.
• Signed and dated written informed consent prior to admission to the study.
• The subject is able to understand and comply with protocol requirements, instructions and protocol-stated restrictions.

Exclusion Criteria:

• Any clinically relevant abnormality identified on the screening medical assessment, laboratory examination, or ECG (12-lead).
• Significant cardiac, pulmonary, metabolic, renal, hepatic, or gastrointestinal conditions that in the opinion of the investigator and/or GSK medical monitor, places the subject at an unacceptable risk as participant in this trial.
• QTc(b) > 450msecs
• A definite or suspected personal or family history of adverse reactions or hypersensitivity to the trial drug or to drugs with a similar chemical structure.
• History of regular alcohol consumption exceeding an average weekly intake of > 21 units (or an average daily intake of greater than 3 units). One unit is equivalent to a half-pint (284mL) of beer/lager; 25mL measure of spirits or 125mL of wine).
• Subjects with a history or presence of gastro-intestinal or renal disease or any other condition known to interfere with the absorption, distribution, metabolism or excretion of drugs.
• Subjects who have consumed grapefruit or grapefruit juice within seven days of the first study day.
• Subjects who have had exposure to more than three new chemical entities within 12 months prior to the first dosing period.
• Subjects who have participated in a trial with a different new chemical entity within 90 days prior to the start of this study.
• If participation in the study will result in the volunteer having donated more than 400mL of blood in the previous 56 days.
• Subjects who have received a total body radiation dose of greater than 5.0 mSv (upper limit of WHO category II) or exposure to significant radiation (e.g. serial X-ray or CT scans, barium meal etc) in the 12 months prior to this study.
• History of elevated blood pressure or blood pressure persistently >140/90 mmHg at screening.
• An unwillingness to abstain from sexual intercourse with pregnant or lactating women; or an unwillingness of the subject to use a condom/spermicide in addition to having their female partner use another form of contraception such as an IUD, diaphragm with spermicide, oral contraceptives, injectable progesterone, sub dermal implants or a tubal ligation if the women could become pregnant from the time of the first dose of the study medication until completion of the follow-up procedures.
• Lack of suitability for participation in this study, for any reason, in the opinion of the investigator.
• Any condition that could interfere with the accurate assessment and recovery of 14C.
• Prescribed or over-the-counter medication within 5 days (or 5 half lives, whichever is longer) prior to the first dosing day, unless the investigator confirms that it will not introduce additional risk or interfere with the study procedures or outcome.
• Liver function tests (ALT, AST, ALP, GammaGT and bilirubin) > upper limit of normal (ULN) at screening
• Positive urine drug screen
• Positive HIV, Hepatitis B or C result at screening.
• History of use of tobacco- or nicotine-containing products within 6 months of screening or a positive urine cotinine screen (urine cotinine > 250ng/ml).