A Double-blind, Placebo-controlled, Study of the Safety, Tolerability, and Pharmacokinetics of Single Ascending Doses of Oral AFA-281 (Phase I Part 1) and Multiple Ascending Doses of Oral AFA-281 (Phase I Part 2) in Healthy Volunteers

Phase I Part 1 (single ascending dose):

Healthy volunteers will be admitted to the clinical research unit on Day -1. There will be five cohorts with 8 subjects per cohort. Six subjects per cohort will receive AFA-281 at one of 4 doses and 2 will receive placebo. Oral capsules will be administered on the morning of Day 1, following a 10-hour fast. Blood draws for assessment of Pharmacokinetic parameters will occur 0.2-1 hr pre-dose and at 0.5-, 1-, 2-, 3-, 4-, 8-, 10, 12-, 16-, 24-, 36-, 48-hr, and up to 72-hr post-dose. Vital signs will be collected at scheduled times following dosing. A 12-lead ECG will be obtained pre-dose and scheduled at 2, 4, 8, 24 hr, and 3- or 4 days post- dose. Various clinical laboratory tests will be drawn on Day -1, within 1 hr prior to dosing, and at scheduled timepoints after dosing while the volunteer is housed in the research center. Subjects of Cohorts 1 - 3 will be released following completion of blood draws and safety assessments up to 48 hours and Cohorts 4 and 5 subjects will return for 72-hour blood draws and Day 4 ECG and safety assessment.

Phase I Part 2 (multiple ascending doses - 14 days):

After assessment of the safety data from the single dose Phase I Part 1, healthy volunteers will be randomized into 3 cohorts with 8 subjects per cohort. Five subjects per cohort will receive AFA-281 and 3 will receive placebo. Oral capsules will be administered in dose titration and split daily dose in fours time daily (QID) for 14 - 21 consecutive days. Routine clinical monitoring will occur as in Part 1. Baseline physical examination, vital signs, clinical lab tests, and ECGs will be performed prior to dosing, at scheduled intervals after dosing, and at the end of the cohort's study period to evaluate the safety and tolerability, and the pharmacokinetic profile of AFA-281. Reports of potential adverse events will be elicited, and vital signs and 12-lead ECG will be measured in a similar manner to Part 1. Similarly, clinical laboratory tests will be drawn prior to and after dosing.