Phase III Study of D9421-C 9 mg in Patients With Active Crohn's Disease in Japan

• Remission (ie, CDAI score of ≤150) after 2-week treatment [ Time Frame: baseline and Week-2 ] [ Designated as safety issue: Yes ]
• Remission (ie, CDAI score of ≤150) after 4-week treatment [ Time Frame: baseline and Week-4 ] [ Designated as safety issue: Yes ]
• Change in CDAI score [ Time Frame: baseline and after 2-week ] [ Designated as safety issue: Yes ]
• Change in CDAI score [ Time Frame: baseline and Week-4 ] [ Designated as safety issue: Yes ]
• Change in CDAI score [ Time Frame: baseline and Week-8 ] [ Designated as safety issue: Yes ]
• Time to the first remission [ Time Frame: up to 8th Week of treatment ] [ Designated as safety issue: Yes ]
• Clinical improvement defined by a remission (ie, CDAI score of ≤150) or a decrease in CDAI score of at least 100 from baseline [ Time Frame: baseline and week-2 ] [ Designated as safety issue: Yes ]
• Clinical improvement defined by a remission (ie, CDAI score of ≤150) or a decrease in CDAI score of at least 100 from baseline [ Time Frame: baseline and week-4 ] [ Designated as safety issue: Yes ]
• Clinical improvement defined by a remission (ie, CDAI score of ≤150) or a decrease in CDAI score of at least 100 from baseline [ Time Frame: baseline and Week-8 ] [ Designated as safety issue: Yes ]
• Clinical improvement defined by a remission (ie, CDAI score of ≤150) or a decrease in CDAI score of at least 70 from baseline [ Time Frame: baseline and Week-2 ] [ Designated as safety issue: Yes ]
• Clinical improvement defined by a remission (ie, CDAI score of ≤150) or a decrease in CDAI score of at least 70 from baseline [ Time Frame: baseline and Week-4 ] [ Designated as safety issue: Yes ]
• Clinical improvement defined by a remission (ie, CDAI score of ≤150) or a decrease in CDAI score of at least 70 from baseline [ Time Frame: baseline and week-8 ] [ Designated as safety issue: Yes ]
• Change in disease specific health-related quality of life (HRQL) as defined by a score of 180-400 on the CDAI by assessment of the Inflammatory Bowel Disease Questionnaire (IBDQ) total score and all sub scores [ Time Frame: baseline and Week-2 ] [ Designated as safety issue: Yes ]
• Change in disease specific health-related quality of life (HRQL) as defined by a score of 180-400 on the CDAI by assessment of the Inflammatory Bowel Disease Questionnaire (IBDQ) total score and all sub scores [ Time Frame: baseline and Week-4 ] [ Designated as safety issue: Yes ]
• Change in disease specific health-related quality of life (HRQL) as defined by a score of 180-400 on the CDAI by assessment of the Inflammatory Bowel Disease Questionnaire (IBDQ) total score and all sub scores [ Time Frame: baseline and Week-8 ] [ Designated as safety issue: Yes ]

The purpose of this study is to evaluate the clinical efficacy of D9421-C 9 mg once daily compared to Mesalazine 1 g three times a day to patients with mild to moderate active Crohn's disease affecting ileum, ileocecal region and/or ascending colon as defined by a score of 180-400 on the Crohn's Disease Activity Index (CDAI) by assessment of the remission after 8-week treatment defined by a CDAI score of ≤ 150.

A multicentre, double-blind, randomised, parallel-group, Phase III study to assess efficacy and safety of D9421-C 9 mg versus Mesalazine 3 g in patients with active Crohn's Disease (CD) in Japan

• Drug: D9421-C capsule 3 mg
  Patients randomised to D9421-C 9 mg will take 3 capsules of D9421-C capsule 3 mg once daily before breakfast and 4 tablets of Mesalazine tablets placebo three times a day after each meal for 8 weeks.
• Drug: Mesalazine tablets
  Patients randomised to Mesalazine 3 g will take 3 capsules of D9421-C capsule placebo once daily before breakfast and 4 tablets of Mesalazine tablets 250 mg three times a day after each meal for 8 weeks.

• Experimental: D9421-C
  D9421-C 9 mg once daily
  Intervention: Drug: D9421-C capsule 3 mg
• Active Comparator: Mesalazine
  Mesalazine 1 g three times a day
  Intervention: Drug: Mesalazine tablets

Inclusion Criteria:

• 15 years of age or older
• Main active disease of the ileal, ileocecal region, and/or ascending colon - - If treated with partial nutrition treatment (≤1200 kcal/day) or if treated with azathioprine (≤2.0 mg/kg/day) or 6-mercaptopurine (≤1.2 mg/kg/day), prior to randomisation until the study completion or discontinuation
• Ability to read, write and to fill a diary card and HRQL questionnaire Having mild to moderate active Crohn's disease, defined as CDAI score of 180-400 at baseline

Exclusion Criteria:

• Patient with CD lesion or status which may affect the evaluation of the efficacy (e.g. lesion only in the upper G-I, active anorectal lesion, abscess formation, stenosis, fistulae, ostomy, short bowel or other uncontrolled concomitant disease)
• Patient who need any concomitant treatment for CD that may affect the assessment for efficacy of the study drug
• Patient who need any medication which is prohibited due to suspected influence to metabolism of the study drug
• Patient who is judged to be inadequate to participate in this study from the safety point of view Patient with well-founded doubt about protocol violation