Scientists test drug binding in healthy lungs to guide future treatments

Copied word for word from the study's registry entry, so the wording is the study team's rather than ours.

Inclusion Criteria: * Subjects aged between 25-75 years old * Able to provide written informed consent prior to any study mandated procedures * Able to lie comfortably on back for up to 90 minutes at a time (Part A only) * Female participants of childbearing potential are eligible to participate after a negative highly sensitive pregnancy test if they are taking a highly effective method of contraception during participation in the study and until the end of relevant systemic exposure. The following methods are permitted: * progesterone implant * intrauterine device (also called IUD) * intrauterine hormone-releasing system (also known as IUS) * bilateral tubal occlusion * vasectomised partner * sexual abstinence * Male participants who are fertile are eligible to participate if they are willing to comply with the contraceptive requirements as listed above \*Definition of fertile females (women of childbearing potential) and of fertile men: For the purpose of this document, a woman is considered of childbearing potential, i.e. fertile, following menarche and until becoming post-menopausal unless permanently sterile. Permanent sterilisation methods include hysterectomy, bilateral salpingectomy and bilateral oophorectomy. A postmenopausal state is defined as no menses for 12 months without an alternative medical cause. A high follicle stimulating hormone (FSH) level in the postmenopausal range may be used to confirm a post-menopausal state in women not using hormonal contraception or hormonal replacement therapy. However in the absence of 12 months of amenorrhea, a single FSH measurement is insufficient. For the purpose of this document, a man is considered fertile after puberty unless their medical notes document that they are permanently sterile. Exclusion Criteria: * Unable to provide informed consent and/or are non-fluent speakers of the English language * Hypersensitivity to XBD173 or to any of the excipients * Clinically-significant renal disease (confirmed by creatinine clearance \<30 ml/min per 1.73m2) * Clinically-significant liver disease (confirmed by serum transaminases \>3 times than upper normal limit) * History of uncontrolled systemic hypertension * Acute infection (including eye, dental, and skin infections) * History of chronic inflammatory disease including HIV, and Hepatitis B * Women who are pregnant or breastfeeding * Patients who have received an Investigational Medicinal Product (IMP) within 5 half-lives of the last dose of the IMP or 1 month (which ever is greater) before the baseline visit * Diagnosis of any condition which may directly or indirectly lead to lung pathology in the opinion of the investigator * Severe and moderate P450 CY3A4 inhibitors o Boceprevir, Clarithromycin, Cobicistat, Idelalisib, Itraconazole, Ketoconazole, Nelfinavir, Ritonavir, Saquinavir, Telaprevir, Telithromycin, Voriconazoleb, Aprepitant, Conivaptan, Crizotinib, Diltiazem, Dronedarone, Erythromycin, Fluconazole, Imatinib, Isavuconazole, Nefazodone, Netupitant, Nilotinib, Posaconazolee, Tofisopam, Verapamil, Delavirdine. * Severe and moderate P450 CY3A4 inducers o Carbamazepine, Enzalutamide, Fosphenytoin, Mitotane, Phenytoin, Rifampicin, Bosentan, Efavirenz, St John's wort, Barbiturates, Nevirapine, Primidone, Rifabutin, Rifapentine. * Part A (PET imaging) specific exclusion criteria * TT/AT Genotype at the rs6971 locus * Previous participation in a research study involving ionising radiation such that in combination with this study the radiation exposure over the last 12 months would exceed 10 mSv * Positive Allen's test * Use of Oral anticoagulants or antiplatelet agents other than low dose aspirin