Evaluation of the Potential for Cytochrome P450 3A4 Inhibition by F901318 Using Oral Midazolam as a Probe

Inclusion Criteria: 1. Subjects will be males of any ethnic origin between 18 and 45 years of age and weighing 60-100 kg inclusive. 2. Subjects must be in good health, as determined by a medical history, physical examination, 12-lead electrocardiogram (ECG) and clinical laboratory evaluations (congenital non haemolytic hyperbilirubinaemia is acceptable). 3. Subjects will have given their written informed consent to participate in the study and to abide by the study restrictions. 4. Subjects must have ophthalmology assessments within the normal limits at screening. This includes normal Meibomian gland function. Exclusion Criteria: 1. Male subjects who are not willing to use appropriate contraception during the study and for three months thereafter. 2. Subjects who have received any prescribed systemic or topical medication within 14 days of the dose administration unless in the opinion of the Investigator and the Medical Monitor the medication will not interfere with the study procedures or compromise safety. 3. Subjects who have used any non-prescribed systemic or topical medication (including herbal remedies) within 7 days of the dose administration (with the exception of vitamin/mineral supplements and paracetamol) unless in the opinion of the Investigator and the Medical Monitor the medication will not interfere with the study procedures or compromise safety. 4. Subjects who have received any medications, including St John's Wort, known to chronically alter drug absorption or elimination processes within 30 days of the dose administration unless in the opinion of the Investigator and the Medical Monitor the medication will not interfere with the study procedures or compromise safety. For at least 2 weeks prior to dosing and until all blood samples and observations are completed on Day 15 +/- 2s, subjects will not be allowed to eat any food or drink any beverage containing alcohol, grapefruit or grapefruit juice, apple or orange juice, vegetables from the mustard green family e.g. kale, broccoli, watercress, spring greens, kohlrabi, Brussels sprouts, mustard and charbroiled meats.