Etrasimod Dose-Ranging Versus Placebo as Induction Therapy Study in Adult Japanese Subjects With Moderately to Severely Active Ulcerative Colitis

Clinical remission:Participants with stool frequency (SF)subscore=0(or of 1 with greater than or equal to(>=)1 point decrease from baseline,rectal bleeding(RB)subscore=0 and endoscopic score(ES)less than or equal to(<)=1(excluding friability).SF subscore:number of stools in 24-hours relative to normal number of stools for that participant in same period,score ranged from 0(normal number of stools) to 3(5 or more stools than normal),higher scores=more severity.RB subscore:most severe amount of blood passed per rectum in 24-hours,score ranged from 0(no blood seen)to 3(blood alone passes),higher scores=more severity.ES:reported worst appearance of mucosa on flexible sigmoidoscopy or colonoscopy,score ranged from 0(normal or inactive disease) to 3(severe disease [spontaneous bleeding,ulceration]),higher scores=more severity.Modified Mayo score:measure disease activity for UC,score:0(normal) to 9(maximum severity),comprised subscores for SF,RB,ES.higher score=more severe disease activity.

Endoscopic improvement was defined as ES <= 1 (excluding friability). ES reported worst appearance of mucosa on flexible sigmoidoscopy or colonoscopy, score ranged from 0 (normal or inactive disease) to 3 (severe disease [spontaneous bleeding, ulceration]), higher scores = more severity. Modified Mayo score (MMS): measure disease activity for UC, score: 0 (normal) to 9 (maximum severity),and comprised the subscores for SF, RB, ES. Higher score = more severe disease activity.

Symptomatic remission was defined as SF sub score = 0 (or = 1 with a >= 1 point decrease from baseline) and RB sub score = 0. SF subscore: reported number of stools in a 24-hour period relative to normal number of stools for that participant in the same period, score ranged from 0 (normal number of stools) to 3 (5 or more stools than normal), higher scores = more severity. RB subscore: reported the most severe amount of blood passed per rectum in a 24-hour period, score ranged from 0 (no blood seen) to 3 (blood alone passes), higher scores = more severity. MMS: measure disease activity for UC, score: 0 (normal) to 9 (maximum severity), and comprised the subscores for SF, RB, ES. Higher score = more severe disease activity.

Mucosal healing was defined as ES <= 1 (excluding friability) with histologic remission defined as a Geboes index score < 2.0). ES reported worst appearance of mucosa on flexible sigmoidoscopy or colonoscopy, score ranged from 0 (normal or inactive disease) to 3 (severe disease [spontaneous bleeding, ulceration]), higher scores = more severity. The Geboes score grading system, was a validated score for evaluating histologic disease activity in UC as follows: grade 0 = structural and architectural changes; grade 1 = chronic inflammatory infiltrate; grade 2 = lamina propria neutrophils and eosinophils; grade 3 = neutrophils in the epithelium; grade 4 = crypt destruction; grade 5 = erosions or ulceration. A higher Geboes score indicated more severe disease. Modified Mayo score (MMS): measure disease activity for UC, score: 0 (normal) to 9 (maximum severity), comprised subscores for SF, RB, ES. Higher score = more severe disease activity.

Clinical response was defined as a >= 2-point and >= 30 percentage (%) decrease from baseline in MMS, and a >= 1-point decrease from baseline in RB subscore or an absolute RB subscore <= 1. MMS: measure disease activity for UC, score: 0 (normal) to 9 (maximum severity), and comprised the subscores for SF, RB, ES. Higher score = more severe disease activity. RB subscore: reported the most severe amount of blood passed per rectum in a 24-hour period, score ranged from 0 (no blood seen) to 3 (blood alone passes), higher scores = more severity.

Endoscopic normalization was defined as ES= 0. ES reported worst appearance of mucosa on flexible sigmoidoscopy or colonoscopy, score ranged from 0 (normal or inactive disease) to 3 (severe disease [spontaneous bleeding, ulceration]), higher scores = more severity. MMS: measure disease activity for UC, score: 0 (normal) to 9 (maximum severity), and comprised the subscores for SF, RB, ES. Higher score = more severe disease activity.

An adverse event was any untoward medical occurrence in a participant or clinical investigational participant administered a medicinal product and which does not necessarily have a causal relationship with this treatment. An adverse event was therefore any unfavorable and unintended sign, symptom, or disease temporally associated with the use of a medicinal product, whether or not considered related to the medicinal product. Severity was classified using common terminology criteria for adverse events (CTCAE), version 5.0, such as Grade 1 for mild, Grade 2 for moderate, Grade 3 for severe, Grade 4 for life-threatening, Grade 5 for death related to adverse event.