Study to Evaluate the Efficacy and Safety of Filgotinib in the Induction and Maintenance of Remission in Adults With Moderately to Severely Active Ulcerative Colitis

EBS remission was defined as an endoscopic subscore of 0 or 1; rectal bleeding subscore of 0; and at least a 1-point decrease in stool frequency from baseline to achieve a subscore of 0 or 1. Endoscopic subscore range: 0 to 3, where 0 = normal or inactive disease and 3 = severe disease (spontaneous bleeding, ulceration); rectal bleeding subscore range: 0 to 3, where 0 = no blood seen and 3 = blood alone passes; stool frequency subscore range: 0 to 3, where 0 = normal number of stools and 3 = at least 5 stools more than normal. Total score for EBS ranged from 0 to 9 (sum of all subscores), with higher scores indicating more severe disease.

EBS remission was defined as an endoscopic subscore of 0 or 1; rectal bleeding subscore of 0; and at least a 1-point decrease in stool frequency from baseline to achieve a subscore of 0 or 1. Endoscopic subscore range: 0 to 3, where 0 = normal or inactive disease and 3 = severe disease (spontaneous bleeding, ulceration); rectal bleeding subscore range: 0 to 3, where 0 = no blood seen and 3 = blood alone passes; stool frequency subscore range: 0 to 3, where 0 = normal number of stools and 3 = at least 5 stools more than normal. Total score for EBS ranged from 0 to 9 (sum of all subscores), with higher scores indicating more severe disease.

MCS remission was defined as having a MCS of 2 or less and no single subscore higher than 1. The MCS was composed of subscores from endoscopy (range: 0 to 3, where 0 = normal or inactive disease and 3 = severe disease [spontaneous bleeding, ulceration]), rectal bleeding (range: 0 to 3, where 0 = no blood seen and 3 = blood alone passes), stool frequency (range: 0 to 3, where 0 = normal number of stools and 3 = at least 5 stools more than normal), and physician's global assessment (PGA). The PGA acknowledged the participant's daily recollection of abdominal discomfort and general sense of wellbeing, and other observations, such as physical findings and the participant's performance status. The PGA score ranged from 0 to 3 with higher score indicating the severe disease. Total score for MCS ranged from 0 to 12 (sum of all subscores), with higher scores indicating more severe disease.

Endoscopic subscore range: 0 to 3, where 0 = normal or inactive disease and 3 = severe disease (spontaneous bleeding, ulceration).

Geboes histologic remission was assessed using the Geboes histologic scores for evaluation of disease severity in ulcerative colitis and classifies histologic changes. Remission was defined as having Grade 0 of <= 0.3, Grade 1 of <= 1.1, Grade 2A of <= 2A.3, Grade 2B of 2B.0, Grade 3 of 3.0, Grade 4 of 4.0, and Grade 5 of 5.0. Possible scores are Grade 0: Architectural changes (0.0=No abnormality to 0.3=Severe diffuse or multifocal abnormalities); Grade 1: Chronic inflammatory infiltrate (1.0=No increase to 1.3=Marked increase); Grade 2A: Eosinophils in lamina propria (2A.0=No increase to 2A.3-=Marked increase; Grade 2B: Neutrophils in lamina propria (2B.0= No increase to 2B.3=Marked increase); Grade 3: Neutrophils in epithelium (3.0=None to 3.3=>50% crypts involved); Grade 4: Crypt destruction (4.0=none to 4.3=Unequivocal crypt destruction), and Grade 5: Erosions and ulcerations: (5.0=No erosion, ulceration or granulation to 5.4=Ulcer or granulation tissue).

MCS remission (alternative definition) was defined as having rectal bleeding, stool frequency, and PGA subscores of 0 and an endoscopic subscore of 0 or 1; overall MCS of ≤ 1. MCS possible subscores: rectal bleeding (range: 0 to 3, where 0 = no blood seen and 3 = blood alone passes), stool frequency (range: 0 to 3, where 0 = normal number of stools and 3 = at least 5 stools more than normal), PGA subscore (range: 0 to 3 with higher score indicating the severe disease), and an endoscopic subscore (range: 0 to 3, where 0 = normal or inactive disease and 3 = severe disease [spontaneous bleeding, ulceration]. Total score for MCS ranged from 0 to 12 (sum of all subscores), with higher scores indicating more severe disease.

Cmax is defined as the maximum observed concentration of drug.

Tmax is defined as the time to reach maximum observed concentration of drug.

AUCtau is defined as concentration of drug over time (the area under the concentration verses time curve over the dosing interval).

AUClast is defined as the concentration of drug from time zero to the last observable concentration.

Ctau is defined as the observed drug concentration at the end of the dosing interval.

MCS remission was defined as having a MCS of 2 or less and no single subscore higher than 1. The MCS was composed of subscores from endoscopy (range: 0 to 3, where 0 = normal or inactive disease and 3 = severe disease [spontaneous bleeding, ulceration]), rectal bleeding (range: 0 to 3, where 0 = no blood seen and 3 = blood alone passes), stool frequency (range: 0 to 3, where 0 = normal number of stools and 3 = at least 5 stools more than normal), and PGA. The PGA acknowledged the participant's daily recollection of abdominal discomfort and general sense of wellbeing, and other observations, such as physical findings and the participant's performance status. The PGA score ranged from 0 to 3 with higher score indicating the severe disease. Total score for MCS ranged from 0 to 12 (sum of all subscores), with higher scores indicating more severe disease.

Sustained EBS remission was defined as having achieved EBS remission at both Weeks 10 and 58.

Six-month corticosteroid-free EBS remission at Week 58 was defined as achieving EBS remission with no corticosteroid use for the indication of ulcerative colitis for at least 6 months prior to Week 58.

Endoscopic subscore range: 0 to 3, where 0 = normal or inactive disease and 3 = severe disease (spontaneous bleeding, ulceration).

Geboes histologic remission was assessed using the Geboes histologic scores for evaluation of disease severity in ulcerative colitis and classifies histologic changes. Remission was defined as having Grade 0 of <= 0.3, Grade 1 of <= 1.1, Grade 2A of <= 2A.3, Grade 2B of 2B.0, Grade 3 of 3.0, Grade 4 of 4.0, and Grade 5 of 5.0. Possible scores are Grade 0: Architectural changes (0.0=No abnormality to 0.3=Severe diffuse or multifocal abnormalities); Grade 1: Chronic inflammatory infiltrate (1.0=No increase to 1.3=Marked increase); Grade 2A: Eosinophils in lamina propria (2A.0=No increase to 2A.3-=Marked increase; Grade 2B: Neutrophils in lamina propria (2B.0= No increase to 2B.3=Marked increase); Grade 3: Neutrophils in epithelium (3.0=None to 3.3=>50% crypts involved); Grade 4: Crypt destruction (4.0=none to 4.3=Unequivocal crypt destruction), and Grade 5: Erosions and ulcerations: (5.0=No erosion, ulceration or granulation to 5.4=Ulcer or granulation tissue).

MCS remission (alternative definition) was defined as having rectal bleeding, stool frequency, and PGA subscores of 0 and an endoscopic subscore of 0 or 1; overall MCS of ≤ 1. MCS possible subscores: rectal bleeding (range: 0 to 3, where 0 = no blood seen and 3 = blood alone passes), stool frequency (range: 0 to 3, where 0 = normal number of stools and 3 = at least 5 stools more than normal), PGA subscore (range: 0 to 3 with higher score indicating the severe disease), and an endoscopic subscore (range: 0 to 3, where 0 = normal or inactive disease and 3 = severe disease [spontaneous bleeding, ulceration]. Total score for MCS ranged from 0 to 12 (sum of all subscores), with higher scores indicating more severe disease.

Plasma concentration is defined as the measured drug concentration of filgotinib and its metabolite GS-829845. Lower limit of quantitation (LLOQ) was defined as 1 ng/mL for analyte filgotinib and 2 ng/mL for analyte GS-829845.