Clinical remission is defined as a Crohn's Disease Activity Index (CDAI) score ≤ 150 points.

The CDAI is used to quantify the symptoms of patients with Crohn's disease and consists of eight factors, each summed after adjustment with a weighting factor. The components of the CDAI are:

• Number of liquid or soft stools each day for 7 days;
• Abdominal pain (graded from 0-3 on severity) each day for 7 days;
• General well-being, subjectively assessed from 0 (well) to 4 (terrible) each day for 7 days;
• Presence of complications;
• Taking Lomotil or opiates for diarrhea;
• Presence of an abdominal mass (0 as none, 2 as questionable, 5 as definite);
• Hematocrit of < 0.47 in men and < 0.42 in women;
• Percentage deviation from standard weight.

The total score ranges from 0 to approximately 600 and with higher scores indicating greater disease activity.

All participants who prematurely discontinued for any reason were considered as not achieving clinical remission.

Induction Study Intention to Treat (ITT) Population, which consisted of all randomized patients in Cohort 1 who received any amount of blinded study drug.

Enhanced clinical response is defined as a CDAI score at least 100 points lower than Baseline. The CDAI is used to quantify the symptoms of patients with Crohn's disease and consists of eight factors, each summed after adjustment with a weighting factor. The components of the CDAI are:

• Number of liquid or soft stools each day for 7 days;
• Abdominal pain (graded from 0-3 on severity) each day for 7 days;
• General well-being, subjectively assessed from 0 (well) to 4 (terrible) each day for 7 days;
• Presence of complications;
• Taking Lomotil or opiates for diarrhea;
• Presence of an abdominal mass (0 as none, 2 as questionable, 5 as definite);
• Hematocrit of < 0.47 in men and < 0.42 in women;
• Percentage deviation from standard weight.

The total score ranges from 0 to 600 with higher scores indicating greater disease activity.

All participants who prematurely discontinued for any reason were considered as not achieving enhanced clinical response.

Induction Study ITT Population

Clinical remission is defined as a CDAI score ≤ 150. The CDAI is used to quantify the symptoms of patients with Crohn's disease and consists of eight factors, each summed after adjustment with a weighting factor. The components of the CDAI are:

• Number of liquid or soft stools each day for 7 days;
• Abdominal pain (graded from 0-3 on severity) each day for 7 days;
• General well-being, subjectively assessed from 0 (well) to 4 (terrible) each day for 7 days;
• Presence of complications;
• Taking Lomotil or opiates for diarrhea;
• Presence of an abdominal mass (0 as none, 2 as questionable, 5 as definite);
• Hematocrit of < 0.47 in men and < 0.42 in women;
• Percentage deviation from standard weight.

The total score ranges from 0 to 600 with higher scores indicating greater disease activity.

All participants who prematurely discontinued for any reason were considered as not achieving clinical remission.

Maintenance Study ITT Population, defined as all randomized participants who received vedolizumab during the Induction Phase and met the protocol definition of clinical response at Week 6, as assessed by the investigator, were randomized, and received any amount of double-blind study drug in the Maintenance Phase.

C-reactive protein (CRP) is a protein found in the blood, the levels of which rise in response to inflammation. Normal concentration in healthy human serum is usually lower than 10 mg/L, slightly increasing with age. Higher levels indicate mild inflammation (10-40 mg/L) and active inflammation (40-200 mg/L).

Induction Study ITT Population; last observation carried forward (LOCF) imputation was used. Baseline CRP was missing for one participant in the placebo group.

Enhanced clinical response is defined as a CDAI score at least 100 points lower than the Baseline value. The CDAI is used to quantify the symptoms of patients with Crohn's disease and consists of eight factors, each summed after adjustment with a weighting factor. The components of the CDAI are:

• Number of liquid or soft stools each day for 7 days;
• Abdominal pain (graded from 0-3 on severity) each day for 7 days;
• General well-being, subjectively assessed from 0 (well) to 4 (terrible) each day for 7 days;
• Presence of complications;
• Taking Lomotil or opiates for diarrhea;
• Presence of an abdominal mass (0 as none, 2 as questionable, 5 as definite);
• Hematocrit of < 0.47 in men and < 0.42 in women;
• Percentage deviation from standard weight.

The total score ranges from 0 to 600 with higher scores indicating greater disease activity.

All participants who prematurely discontinued for any reason were considered as not achieving enhanced clinical response.

Maintenance Study ITT Population

Participants using oral corticosteroids at Baseline, who discontinued corticosteroids and were in clinical remission (CDAI score ≤ 150) at Week 52 achieved corticosteroid-free clinical remission. The CDAI quantifies the symptoms of patients with Crohn's disease and consists of eight factors, summed after adjustment with a weighting factor. The total score ranges from 0 to 600 with higher scores indicating greater disease activity.

All participants who prematurely discontinued for any reason were considered as not achieving corticosteroid-free clinical remission.

Maintenance Study ITT Population, participants who were on corticosteroids at Baseline.

Durable clinical remission is defined as CDAI score ≤ 150 points at 80% or more of study visits during the Maintenance Phase, including the Week 52 visit (11 of 13 study visits). The CDAI quantifies the symptoms of patients with Crohn's disease and consists of eight factors, summed after adjustment with a weighting factor. The total score ranges from 0 to 600 with higher scores indicating greater disease activity.

All participants who prematurely discontinued for any reason were considered as not achieving durable clinical remission

Maintenance Study ITT Population