An Extension Study for Treatment of Moderately to Severely Active Ulcerative Colitis

Inclusion Criteria:

• Must have met the eligibility criteria and have been enrolled in the qualified Phase 2 or 3 parent studies listed below or other qualified region-specific studies andmeet the following additional criteria:

1. Participants previously enrolled in Study APD334-301 (NCT03945188) orAPD334-210 (NCT04607837) must have completed the Week 12 visit and have beenassessed to have active UC that has not improved or has worsened from baselineor completed the Week 52 visit

2. Participants previously enrolled in APD334-302 (NCT03996369) must havecompleted the Week 12 visit

Exclusion Criteria:

• If Investigator considers the participant to be unsuitable for any reason toparticipate in the Open-Label Extension study

• Experienced an adverse event that led to discontinuation from parent study