On Day 1, patients who meet all entry criteria and none of the exclusion criteria will be randomized to receive either APL-1401 or placebo in a 5:1 ratio. Patients will receive APL-1401 orally once daily (QD) during the 28-day treatment period.~Three cohorts with increasing doses of APL-1401 will be explored. The dose of APL-1401 will start at 120 mg QD in Cohort 1 and sequentially increase to 160 mg QD and 200 mg QD in Cohort 2 and Cohort 3, respectively. Three cohorts with increasing doses of APL-1401 will be explored. 200mg QD is designed to be maximum dose in this study.~In one cohort, if dose stopping criteria of cohort is not met, Safety Monitoring Committee (SMC) will be held when last patient completes 28-day of study treatment. SMC will determine whether to continue the study to next cohort base on pre-defined dose escalation criteria, safety data, and available PK data. At this dose strength, if patients are well tolerated and SMC decides to escalate to a higher dose, the next cohort will be started.
This is a randomized, double-blind, placebo-controlled, phase 1b study designed to evaluate safety, tolerability, PK, and preliminary efficacy of APL-1401 in patients with moderately to severely active UC. This study comprises 3 periods including screening period (D-28~D-1), treatment period (D1-D28), and safety follow-up period(D29-D58).