Conditions: Ankylosing Spondylitis (AS)
Allocation: RANDOMIZED | Intervention model: PARALLEL
Enrollment: 159
Healthy volunteers: no

Brief summary:
The overall purpose of the trial is to assess the clinical efficacy of three different subcutaneous doses of BI 655066 (risankizumab) in adult patients with AS, in order to provide clinical proof of concept and to select dose (s) for confirmatory clinical trials.

Detailed description:

Arms:
arm 1: Subcutaneous injection of Placebo (solution for injection matching risankizumab, 1 mL pre-filled syringe) administered every 8 weeks (At Day1 and at Weeks 8, 16, and 24) up to 4 times during the regular treatment period. arm 2: Subcutaneous injection of risankizumab 18 mg administered every 8 weeks at Day 1 only, followed by placebo every 8 weeks (i.e. at Week 8, 16 and 24), up to a total duration of 24 weeks arm 3: Subcutaneous injection of risankizumab 90 mg administered every 8 weeks (At Day1 and at Weeks 8, 16, and 24) up to 4 times during the regular treatment period arm 4: Subcutaneous injection of risankizumab 180 mg administered every 8 weeks (At Day1 and at Weeks 8, 16, and 24) up to 4 times during the regular treatment period

Interventions: intervention 1: placebo for risankizumab intervention 2: risankizumab
Intervention descriptions: intervention 1: Placebo for risankizumab administered by subcutaneous (SC) injection intervention 2: Risankizumab administered by subcutaneous (SC) injection

Protocol document: