Phase I Single Ascending Dose and Multiple Ascending Doses of Oral AFA-281 in Healthy Volunteers

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): Double-blind dosing will occur in healthy volunteers in 5 cohorts of 8 subjects each. Six subjects in each cohort will be randomized to receive AFA-281 and 2 subjects will be randomized to receive the matching placebo. At the end of the Part 1 study is to evaluate the safety and tolerability of AFA-281. Following completion of each cohort, bioanalytical analyses will be conducted to evaluate the pharmacokinetic profile. Phase I Part 2 (multiple dose for 14 days): Pending the results from Part 1, healthy volunteers will be administered AFA-281 for 14 consecutive days in 3 cohorts. At scheduled intervals after dosing, and at the end of the cohort's study period to evaluate the safety and tolerability of AFA-281 and the pharmacokinetic profile of AFA-281.

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. Five subjects per cohort will receive AFA-281 at either 20, 40, 80, 160 or 300 mg and 3 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 twice daily for 14 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 of AFA-281 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.

Part 1: AFA-281 administered as an oral capsule at 5 dose levels for one day. Part 2: AFA-281 administered as an oral capsule at 3 dose levels twice daily for 14 consecutive days. Doses will be determined after completion of Part 1.

Part 1: AFA-281 will be administered as a single dose at 5 dose levels (TBD) Part 2: AFA-281 will be administered twice daily for 14 days at 3 dose levels (TBD)

Inclusion Criteria: Participants must be in good general health with no significant medical history and have no clinically significant abnormalities on physical examination at screening and/or before administration of the initial dose of study drug. Participants must have a Body Mass Index (BMI) between 18.0 and 30.0 kg/m2 inclusive. Participants must have clinical laboratory values within normal range as specified by the testing laboratory, unless deemed not clinically significant by the Investigator or delegate. Participants must have an ECG without clinically significant pathologic abnormalities. Exclusion Criteria: Participants with significant medical history or clinically significant abnormalities Participants with clinically significantly pathologic abnormalities Participants with ECG abnormalities