A Phase 1, Dose-Escalation Study in Healthy Volunteers to Evaluate the Pharmacokinetics, Safety, and Tolerability of GS-1427 Following Single and Multiple Dosing

INTERVENTION: Two parts: ‐ Part A: 5 cohorts Single Ascending Dose TBD during the study ‐ Part B: 5 cohorts Multiple ascending dose based on Part A Mode of administration ‐ oral capsule The adherence is completed by the site staff watching the participant take the drug and swallow it and then doing a visual check of their mouth to ensure it has been swallowed. Part A Cohort 1: GS‐1427 single dose on Day 1 ‐ 20mg Cohort 2: GS‐1427 single dose on Day 1 ‐ Upto 60mg Cohort 3: GS‐1427 single dose on Day 1 ‐ Upto 200mg Cohort 3: GS‐1427 single dose on Day 8 ‐ Upto 200mg Cohort 4: GS‐1427 single dose on Day 1 ‐ Upto 500mg Cohort 5: GS‐1427 single dose on Day 1 ‐ Upto 100mg Part B Cohort 6: GS‐1427 twice daily for 14 days ‐ Dose TBD Cohort 7: GS‐1427 twice daily for 14 days ‐ Dose TBD Cohort 8: GS‐1427 twice daily for 14 days ‐ Dose TBD Cohort 9: GS‐1427 twice daily for 14 days ‐ Dose TBD Cohort 10: GS‐1427 once daily for 14 days ‐ Dose TBD CONDITION: Inflammatory bowel disease; ; Inflammatory bowel disease Oral and Gastrointestinal ‐ Inflammatory bowel disease PRIMARY OUTCOME: To characterize Cmax and AUC of GS‐1427 in plasma [Part A; Cohorts 1, 2, 4 & 5 ‐ Day 1 = 0.5, 1, 2, 3, 4, 6, 9, 12, 18, 24, 36, 48, 72, and 96 hours post dose; Cohort 3 ‐ Days 1 & 8 = 0.5, 1, 2, 3, 4, 6, 9, 12, 18, 24, 36, 48, 72, and 96 hours post dose; ; Part B; Cohorts 6‐10 ‐ ; Day 1 = 0.5, 1, 2, 3, 4, 6, 9, 12, 18, and 24 hours post dose and; Day 14 = 0.5, 1, 2, 3, 4, 6, 9, 12, 18, 24, 36, 48, 72, and 96 hours post dose; ] SECONDARY OUTCOME: To evaluate the safety and tolerability of escalating single and multiple oral doses of GS‐1427 Following Single and Multiple Dosing ; Adverse events assessed in accordance with the Common Terminology Criteria for Adverse Events (CTCAE5.0)[Part A ; Cohorts 1, 2, 4 & 5 ‐ Day 1 ; Cohort 3 ‐ Days 1 & 8 ; ; Part B ; Cohorts 6‐10 ‐ Days 1, 3,4,5,9,13 and 14] INCLUSION CRITERIA: ‐ Be a non‐smoker. The use of nicotine or nicotine‐containing products must be discontinued 90 days prior to the first dose of study drug ‐ Have a calculated body mass index (BMI) of >19 and < 30 kg/m2 at screening ‐ Must be willing and able to comply with all study requirements ‐ Must, in the opinion of the investigator, be in good health based upon medical history and physical examination, including vital signs