Conditions: Crohn's Disease
Keywords: IBD, Crohn's Disease
Allocation: RANDOMIZED | Intervention model: PARALLEL
Enrollment: 254
Healthy volunteers: no

Brief summary:
The primary objective of this study is to evaluate the efficacy of abrilumab as measured by the proportion of participants achieving Crohn's Disease Activity Index (CDAI) remission (CDAI \< 150) after treatment for 8 weeks.

Detailed description:
The study consisted of a 24-week double-blind treatment period, a 108-week open-label treatment period, and a 2-year safety follow-up period.

Participants who did not reach minimal improvement, or experienced disease worsening after initial response, had the option to receive open-label abrilumab 210 mg every 3 months (Q3M) beginning at double-blind period week 12 or after. Not reaching minimal improvement was defined as not having an improvement in CDAI score of ≥ 70 points from baseline on 2 consecutive visits (at or after week 8) at least 2 weeks apart. Disease worsening after week 8 (or week 12) response was defined as having an increase in CDAI score of ≥ 70 points from the week 8 (or week 12) CDAI score on 2 consecutive visits at least 2 weeks apart, and a CDAI score of \> 150.

Participants were planned to be randomized in a 2:1:2:1 ratio to SC placebo or abrilumab at 21 mg, 70 mg (on day 1, week 2, week 4, and every 4 weeks thereafter until week 24), or 210 mg (on day 1 followed by placebo in weeks 2 and 4 and every 4 weeks thereafter until week 24), respectively. Due to a consistent discrepancy between the investigational product (IP) instruction manual (IPIM) description of vial positions and the actual vial positions in the IP package participants were initially randomized to 3 arms (placebo, 70 mg, and 210 mg) with a randomization ratio of 3:2:1. The study was temporarily paused while this issue was investigated. Once the discrepancy was corrected, Protocol Amendment 3 implemented, and affected participants completed their double-blind treatment period, the study resumed enrollment and randomization per protocol. Neither the randomization nor study blind was compromised and therefore the intent-to-treat principle was maintained.

Arms:
arm 1: Participants received placebo by subcutaneous injection on day 1, week 2, week 4, and every 4 weeks thereafter until week 24.

During the open-label period, participants received abrilumab 210 mg once every 3 months (Q3M) for 108 weeks. arm 2: Participants received 21 mg abrilumab by subcutaneous injection on day 1, week 2, week 4, and every 4 weeks (Q4W) thereafter until week 24.

During the open-label period, participants received abrilumab 210 mg once every 3 months (Q3M) for 108 weeks. arm 3: Participants received 70 mg abrilumab by subcutaneous injection on day 1, week 2, week 4, and every 4 weeks thereafter until week 24.

During the open-label period, participants received abrilumab 210 mg once every 3 months (Q3M) for 108 weeks. arm 4: Participants received a single dose of 210 mg abrilumab by subcutaneous injection on day 1, followed by placebo at week 2, week 4, and every 4 weeks thereafter until week 24.

During the open-label period, participants received abrilumab 210 mg once every 3 months (Q3M)for 108 weeks.

Interventions: intervention 1: Abrilumab intervention 2: Placebo
Intervention descriptions: intervention 1: Administered by subcutaneous injection. intervention 2: Placebo matching to abrilumab administered by subcutaneous injection

Protocol document: