A Study of Vedolizumab in Children and Teenagers With Moderate to Severe Ulcerative Colitis (UC)

Clinical remission based on the modified Mayo score was defined as stool frequency sub score 0 to 1 and a decrease of 1 or more from baseline, rectal bleeding sub score of 0, and endoscopy sub score 0 to 1 (modified so that a score of 1 does not include friability) and without presence of any intercurrent event. Mayo score was an instrument designed to measure disease activity of UC. Modified Mayo score was a composite index of 3 disease activity variables (stool frequency, rectal bleeding, and endoscopy). Each subscale was graded from 0 to 3 where higher score indicated more severe disease. These scores were summed to give a total score range of 0 to 9 where, higher score indicated more severe disease.

Clinical remission based on the modified Mayo score was defined as stool frequency sub score 0 to 1 and a decrease of 1 or more from baseline, rectal bleeding sub score of 0, and endoscopy sub score 0 to 1 (modified so that a score of 1 does not include friability) and without presence of any intercurrent event. Mayo score was an instrument designed to measure disease activity of UC. Modified Mayo score was a composite index of 3 disease activity variables (stool frequency, rectal bleeding, and endoscopy. Each subscale was graded from 0 to 3 where higher score indicated more severe disease. These scores were summed to give a total score range of 0 to 9 where, higher score indicated more severe disease.

Participants who had clinical remission at Week 14 were analyzed for sustained clinical remission at Week 54. Clinical remission based on the modified Mayo score was defined as stool frequency sub score 0 to 1 and a decrease of 1 or more from baseline, rectal bleeding sub score of 0, and endoscopy sub score 0 to 1 (modified so that a score of 1 does not include friability) and without presence of any intercurrent event. Mayo score was an instrument designed to measure disease activity of UC. Modified Mayo score was a composite index of 3 disease activity variables (stool frequency, rectal bleeding, and endoscopy. Each subscale was graded from 0 to 3 where higher score indicated more severe disease. These scores were summed to give a total score range of 0 to 9 where, higher score indicated more severe disease.

Participants who had endoscopic remission at Week 14 were analyzed for sustained endoscopic remission at Week 54. Mayo endoscopic sub score (MES) was a subscale of the Mayo score, an instrument designed to measure disease activity of UC. The subscale was graded from 0 to 3 based on the findings on endoscopy where 0=normal or inactive disease, 1=mild disease (erythema, decreased vascular pattern), 2=moderate disease (marked erythema, lack of vascular pattern, friability, erosions), 3=severe disease (spontaneous bleeding, ulceration). Higher score indicated more severe disease.

Endoscopic response was defined as a decrease from baseline in the MES >=1 point. MES was a subscale of the Mayo score, an instrument designed to measure disease activity of UC. The subscale was graded from 0 to 3 based on the findings on endoscopy where 0=normal or inactive disease, 1=mild disease (erythema, decreased vascular pattern), 2=moderate disease (marked erythema, lack of vascular pattern, friability, erosions), 3=severe disease (spontaneous bleeding, ulceration). Higher score indicated more severe disease.

Endoscopic response was defined as a decrease from baseline in the MES >=1 point. MES was a subscale of the Mayo score, an instrument designed to measure disease activity of UC. The subscale was graded from 0 to 3 based on the findings on endoscopy where 0=normal or inactive disease, 1=mild disease (erythema, decreased vascular pattern), 2=moderate disease (marked erythema, lack of vascular pattern, friability, erosions), 3=severe disease (spontaneous bleeding, ulceration). Higher score indicated more severe disease.

Corticosteroid-free clinical remission based on the modified Mayo score was defined as when a participant meets the definition described in the primary endpoint and was off corticosteroids at least 12 weeks prior to and at Week 54 and without presence of any intercurrent event. Modified Mayo score was a composite index of 3 disease activity variables (stool frequency, rectal bleeding, and endoscopy. Each subscale was graded from 0 to 3 where higher score indicated more severe disease. These scores were summed to give a total score range of 0 to 9 where, higher score indicated more severe disease.

Clinical remission based on complete Mayo score was a score (inclusive of physician global assessment [PGA]) of <=2 points with no individual sub score >1 and without presence of any intercurrent event. Mayo score was an instrument designed to measure disease activity of UC. Complete Mayo score was a composite index of 4 disease activity variables (stool frequency, rectal bleeding, endoscopy [modified so that a score of 1 does not include friability], and PGA sub scores) ranging from 0-12. Higher score indicated more severe disease.

Serum trough concentration of vedolizumab was reported.

AVA positive was defined as a confirmed AVA positive result.

Positive Neutralizing AVA was defined as a positive result in the neutralizing AVA assay at any visit.

Participants who had clinical response at Week 14 were analyzed for sustained clinical response at Week 54. Sustained refers to meeting the specific endpoint criteria at both Week 14 and Week 54. Sustained clinical response is defined as meeting the following criteria at both Week 14 and Week 54: reduction in complete Mayo score of >=3 points and >=30% from baseline with an accompanying decrease in rectal bleeding sub score of >=1 point or absolute rectal bleeding sub score of <=1 point. Mayo score was an instrument designed to measure disease activity of UC. Complete Mayo score was a composite index of 4 disease activity variables (stool frequency, rectal bleeding, endoscopy [modified so that a score of 1 does not include friability], and PGA sub scores) ranging from 0-12. Higher score indicated more severe disease.

Clinical response was where a participant achieved clinical response if they had a reduction of >=2 points and >=25% from the baseline partial Mayo score, including a >=1 point decrease in the Mayo stool frequency sub score and a >=1 point reduction in the rectal bleeding sub score or absolute rectal bleeding sub score of <=1 point. Mayo score was an instrument designed to measure disease activity of UC. A partial Mayo score was defined as composite index of 3 disease activity variables (stool frequency, rectal bleeding, and PGA sub scores) that ranged from 0-9 and excluded the endoscopy sub score. Higher score indicates more severe disease.

Clinical remission based on partial Mayo score was defined as a partial Mayo score of <=2 points and no individual sub score >1 point. Mayo score was an instrument designed to measure disease activity of UC. A partial Mayo score was defined as composite index of 3 disease activity variables (stool frequency, rectal bleeding, and PGA sub scores) that ranged from 0-9 and excluded the endoscopy sub score. Higher score indicates more severe disease.

A TEAE was defined as an AE whose date of onset occurred on or after the first dose of study drug through Week 54 for participants entering the extension study or the final safety visit 18 weeks after their last dose of study drug for those who do not enter the extension study or those who early terminate. A TESAE was defined as an undesirable event that was not present prior to medical treatment or an already present event that worsened either in intensity or frequency following the first dose of study drug, that occurred from the first dose of study drug to the day of last dose of study drug + 126 days. AESI was defined as an AE (serious or nonserious) of medical concern specific to the compound or program, for which ongoing monitoring and rapid communication by the investigator to the sponsor was appropriate. AESIs include infusion-related reactions and hypersensitivity, serious infection, malignancy, or other (liver injury and progressive multifocal leukoencephalopathy [PML]).

Change from baseline in weight was reported.

Change from baseline in weight Z-score was reported. Weight z-score expresses how an individual's measured weight compares to the expected weight of a reference population of the same age and sex, standardized using population growth charts. It represents the number of standard deviations (SDs) an individual's weight is above or below the mean of the reference population. Z-score was calculated as: Z-score = (observed value - median value of the reference population) / standard deviation value of reference population. A Z-score of 0 represents the mean of the reference population. A negative Z-score indicates that the observed value is below (lower than) the reference mean, while a positive Z-score indicates that the observed value is above (higher than) the reference mean.

Change from baseline in height was reported.

Change from baseline in linear growth Z-score were reported. Linear growth Z-score is a standardized measure that describes how far a measured height deviates from the median height of a reference population of the same age and sex based on established growth charts. It is expressed in units of standard deviations (SD). Z-score was calculated as: Z-score = (observed value - median value of the reference population) / standard deviation value of reference population. A Z-score of 0 represents the mean of the reference population. A negative Z-score indicates that the observed value is below (lower than) the reference mean, while a positive Z-score indicates that the observed value is above (higher than) the reference mean.

Tanner stages are used to evaluate growth parameters. They are standardized for age, sex, and pubertal development, with Stage 1 representing the prepubertal stage and Stage 5 representing the fully mature adult stage. It measures Female pubertal development staged by pubic hair development and breast size; male pubertal development staged by size of the genitalia and development of pubic hair. Rated in 5 stages: stage 1 (no development) to 5 (adult-like development in quantity and size). The data reported shows shifts in participants' Tanner stages from baseline to Week 54.