The CDAI was used to evaluate the activity of Crohn's disease. Clinical remission per CDAI is defined as CDAI <150. The CDAI is calculated on the basis of a one-week evaluation of 8 items: frequency of liquid or very soft stool, abdominal pain, complications of Crohn's disease (e.g., uveitis, arthritis, fistula, and abscess), abdominal mass, hematocrit, body weight, use of antidiarrheals, and general condition. Total score ranges from 0 to about 600. Higher CDAI scores indicate more severe disease. CDAI scores below 150 represent remission and scores over 450 represent very severe Crohn's disease. Results were based on non-responder imputation incorporating multiple imputation to handle missing data due to COVID-19 (NRI-C).

ITT1 Population included all randomized participants who received at least one dose of DB study drug during Part 1.

Endoscopic response was defined as greater than 50% decrease in Simple Endoscopic Score for Crohn's Disease (SES-CD) from Baseline of the induction study (or for participants with an SES-CD of 4 at Baseline of the induction study, at least a 2-point reduction from Baseline), as scored by Central Reviewer. SES-CD is calculated based on the sum of individual segment values for four endoscopic variables (presence and size of ulcers, ulcerated surface, affected surface and presence of narrowing). Each variable in each segment is scored 0 to 3 resulting in SES-CD values ranging from 0 to 56 with higher scores indicating more severe disease. Results were based on NRI-C.

ITT1 Population included all randomized participants who received at least one dose of DB study drug during Part 1.

An adverse event (AE) is defined as any untoward medical occurrence in a patient or clinical investigation participant administered a pharmaceutical product and which does not necessarily have a causal relationship with this treatment. An AE can therefore be any unfavorable and unintended sign (including an abnormal laboratory finding), symptom, or disease temporally associated with the use of a medicinal (investigational) product, whether or not the event is considered causally related to the use of the product.

Safety Population for Part 1 (SA1)=all participants who received at least one dose of the study drug in Part 1,SA2=all participants who received at least one dose of the study drug in Part 2, and SA3=all participants who received at least one dose of the study drug (upadacitinib 30 mg or upadacitinib 45 mg) in Part 3.

Clinical remission per PROs was defined as average daily very soft or liquid stool frequency (SF) ≤2.8 and average daily abdominal pain (AP) score ≤1.0 and both not greater than Baseline. The number of soft or liquid stools and abdominal pain rated on a scale of 0=none to 3=severe were recorded in an electronic diary. Results were based on NRI-C.

ITT1 Population included all randomized participants who received at least one dose of DB study drug during Part 1.

Endoscopic remission was defined per SES-CD. SES-CD ≤4 and at least 2-point reduction from Baseline and no subscore >1 in any individual variable, as scored by Central Reviewer. SES-CD is calculated based on the sum of individual segment values for four endoscopic variables (presence and size of ulcers, ulcerated surface, affected surface and presence of narrowing). Each variable in each segment is scored 0 to 3 resulting in SES-CD values ranging from 0 to 56 with higher scores indicating more severe disease. Results were based on NRI-C.

ITT1 Population included all randomized participants who received at least one dose of DB study drug during Part 1.

As prespecified in the protocol, this outcome measure was planned to be assessed in participants taking corticosteroids at Baseline. Clinical remission per CDAI: CDAI <150. The CDAI is used to evaluate the activity of Crohn's disease. The CDAI is calculated on the basis of a one-week evaluation of 8 items: frequency of liquid or very soft stool, abdominal pain, complications of Crohn's disease (e.g., uveitis, arthritis, fistula, and abscess), abdominal mass, hematocrit, body weight, use of antidiarrheals, and general condition. Total score ranges from 0 to about 600. Higher CDAI scores indicate more severe disease. CDAI scores below 150 represent remission and scores over 450 represent very severe Crohn's disease. Results were based on NRI-C.

ITT1 Population included all randomized participants who received at least one dose of DB study drug during Part 1. Overall Number of Participants Analyzed are the number of participants taking corticosteroids at Baseline.

The FACIT-F questionnaire was developed to assess fatigue associated with anemia. It consists of 13 fatigue-related questions. The responses to the 13 items on the FACIT-F questionnaire are each measured on a 5-point Likert scale. The responses to the answers are the following: 0= not at all; 1= a little bit; 2= somewhat; 3= quite a bit; 4=very much. Thus, the total score ranges from 0 to 52. High scores represent less fatigue. A positive change from Baseline indicates improvement.

ITT1 Population included all randomized participants who received at least one dose of DB study drug during Part 1. Overall Number of Participants Analyzed are the number of participants with data available at the given timepoint.

The IBDQ is a disease-specific instrument composed of 32 Likert-scaled items. The IBDQ scale contains 4 component subscales: bowel symptoms (10 items), systemic symptoms (5 items), emotional function (12 items), and social function(5 items). Each item is scored on a 7-point scale where: 1=worst to 7= best. The total score ranges from 32 to 224, with higher scores indicating better health-related quality of life. A positive change from Baseline indicates improvement.

ITT1 Population included all randomized participants who received at least one dose of DB study drug during Part 1. Overall Number of Participants Analyzed are the number of participants with data available at the given timepoint.

CR-100 is defined as a decrease of at least 100 points in CDAI from Baseline at Week 2. The CDAI is used to evaluate the activity of Crohn's disease. The CDAI is calculated on the basis of a one-week evaluation of 8 items: frequency of liquid or very soft stool, abdominal pain, complications of Crohn's disease (e.g., uveitis, arthritis, fistula, and abscess), abdominal mass, hematocrit, body weight, use of antidiarrheals, and general condition. Total score ranges from 0 to about 600. Higher CDAI scores indicate more severe disease. CDAI scores below 150 represent remission and scores over 450 represent very severe Crohn's disease. Results were based on NRI-C.

ITT1 Population included all randomized participants who received at least one dose of DB study drug during Part 1.

CR-100 is defined as a decrease of at least 100 points in CDAI from Baseline at Week 12. The CDAI is used to evaluate the activity of Crohn's disease. The CDAI is calculated on the basis of a one-week evaluation of 8 items: frequency of liquid or very soft stool, abdominal pain, complications of Crohn's disease (e.g., uveitis, arthritis, fistula, and abscess), abdominal mass, hematocrit, body weight, use of antidiarrheals, and general condition. Total score ranges from 0 to about 600. Higher CDAI scores indicate more severe disease. CDAI scores below 150 represent remission and scores over 450 represent very severe Crohn's disease. Results were based on NRI-C.

ITT1 Population included all randomized participants who received at least one dose of DB study drug during Part 1.

The CDAI was used to evaluate the activity of Crohn's disease. Clinical remission per CDAI is defined as CDAI <150. The CDAI is calculated on the basis of a one-week evaluation of 8 items: frequency of liquid or very soft stool, abdominal pain, complications of Crohn's disease (e.g., uveitis, arthritis, fistula, and abscess), abdominal mass, hematocrit, body weight, use of antidiarrheals, and general condition. Total score ranges from 0 to 600. Higher CDAI scores indicate more severe disease. CDAI scores below 150 represent remission and scores over 450 represent very severe Crohn's disease. Results were based on NRI-C.

ITT1 Population included all randomized participants who received at least one dose of DB study drug during Part 1.

ITT1 Population included all randomized participants who received at least one dose of DB study drug during Part 1.

EIMs are defined as manifestations of Crohn's disease in areas of the body other than the digestive tract, including eyes, skin, joints, mouth, and liver. Results were based on NRI-C.

ITT1 Population included all randomized participants who received at least one dose of DB study drug during Part 1. Overall Number of Participants Analyzed are the number of participants with any EIMs at Baseline.