Positron Emission Tomography (PET) Study to Evaluate Biodistribution of [11C]-GSK2256098 in Healthy Subjects and Idiopathic Pulmonary Arterial Hypertension (PAH) Patients

Inclusion Criteria

Inclusion criteria for healthy volunteers

• Healthy subjects enrolled between 40 to 70 years inclusive at the time of signing the informed consent. Healthy subjects will be recruited to be age (+/-5 years) and gender matched to idiopathic PAH patients.
• Healthy as determined by the investigator or medically qualified designee based on a medical evaluation including medical history, physical examination, laboratory tests and cardiac monitoring.
• Normal spirometry at Screening (forced expiratory volume in 1 second [FEV1] and forced vital capacity [FVC] >= 80% of predicted - measurements to be taken in triplicate and the highest value must be >= 80% of predicted).
• A subject with a clinical abnormality or laboratory parameter(s) outside the reference range for the population being studied may be included only if the investigator, in consultation with the medical monitor if deemed necessary, agree and document that the finding is unlikely to introduce additional risk factors and will not interfere with the study procedures.
• Subject is ambulant and capable of attending for PET- computed tomography (CT) imaging.
• A negative Allen's test in at least one arm for arterial blood sampling (indicating adequate collateral circulation to the hand from both the radial and ulnar arteries).
• Body weight >=50 kg and body mass index (BMI) within the range 18.5 - 35 kilogram/meter^2 (kg/m^2) (inclusive).
• Male or Female A. Males: Male subjects with female partners of child bearing potential must comply with the following contraception requirements from the time of first dose of study medication until 3 months after the scan. In addition, they must not plan to father a child, or donate sperm, for 3 months after the scan.
• Vasectomy with documentation of azoospermia.
• Male condom plus partner use of one of the contraceptive options below:
• Contraceptive subdermal implant
• Intrauterine device or intrauterine system
• Oral Contraceptive, either combined or progestogen alone Injectable progestogen
• Contraceptive vaginal ring
• Percutaneous contraceptive patches

B. Females:

a. Non-reproductive potential defined as: Pre-menopausal females with one of the following; i) Documented tubal ligation ii) Documented hysteroscopic tubal occlusion procedure with follow-up confirmation of bilateral tubal occlusion iii) Hysterectomy iv) Documented Bilateral Oophorectomy Postmenopausal defined as 12 months of spontaneous amenorrhea in questionable cases a blood sample with simultaneous follicle stimulating hormone (FSH) and estradiol levels consistent with menopause. Females on hormone replacement therapy (HRT) and whose menopausal status is in doubt will be required to use one of the highly effective contraception methods if they wish to continue their HRT during the study. Otherwise, they must discontinue HRT to allow confirmation of post-menopausal status prior to study enrolment.

• Capable of giving signed informed consent which includes compliance with the requirements and restrictions listed in the consent form and in this protocol.

Inclusion criteria for PAH Patients:

• PAH patients enrolled between 40 to 70 years inclusive at the time of signing the informed consent.
• Subjects medically diagnosed with idiopathic and inherited PAH, and clinically Functional Class II-IV.
• Subject is ambulant and capable of attending for PET-CT imaging.
• A negative Allen's test in at least one arm for arterial blood sampling (indicating adequate collateral circulation to the hand from both the radial and ulnar arteries).
• Body weight >=50 kg and BMI within the range 18.5 - 35 kg/m^2 (inclusive).
• Male or Female

A. Males:

• Male subjects with female partners of child bearing potential must comply with the following contraception requirements from scan until 3 months after the last dose of study medication. In addition, they must not plan to father a child, or donate sperm, for 3 months after the scan.
• Vasectomy with document