A Phase I, open label study evaluating safety, tolerability and pharmacokinetics of F901318 in healthy subjects following up to 28 days dosing, where F901318 is given orally . The effect of food upon the pharmacokinetics of F901318 and the effect of F901318 upon the pharmacokinetics of midazolam will also be assessed.

Each cohort will comprise 12 healthy subjects and cohorts A1 (A2), B1 and B2 will be conducted in a sequential manner such that the dose level can be optimised upon review of emerging safety, tolerability and PK data.

Inclusion Criteria:

• Subjects will be males or females of any ethnic origin between 18 and 55 years of age, weighing between 60 and 100 kg, with a body mass index (BMI) between 18 and 30 kg/m2.
• 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 not acceptable)
• Male subjects and female subjects of childbearing potential must agree to use appropriate contraception from screening, during the study and for 3 months after the last dose of study drug

Exclusion Criteria:

• Female subjects who are pregnant or lactating.
• Subjects who have received any prescribed systemic or topical medication (other than hormonal contraception or hormone replacement therapy) 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.
• 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) unless in the opinion of the Investigator and the medical monitor the medication will not interfere with the study procedures or compromise safety.
• 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.