Investigate Effect of Secukinumab on the PK of Midazolam in Patients With Mod to Sev Plaque Psoriasis

This will be an open-label, confirmatory study investigating potential disease-drug-drug interaction of secukinumab and midazolam in male and female patients with moderate-to-severe plaque psoriasis. A total of approximately 25 patients are required to obtain at least 20 completers in the study Patients who meet the eligibility criteria at screening, will have a baseline assessment day (within 1 week prior to the start of secukinumab) during which a full midazolam PK profile after a single oral dose of 5 mg will be assessed by collecting blood over the 12 hour postdose period. On Day 1 (Week 0), Day 8 (Week 1), Day 15 (Week 2), Day 22 (Week 3) and Day 29 (Week 4) patients will receive 300 mg s.c. secukinumab (2 injections of 150 mg s.c.). On Day 8 and on Day 36 (Week 5), patients will receive additional single doses of 5 mg oral midazolam (total of 3 single doses). The midazolam PK profile will be assessed over the 12 hour postdose period. On those days when midazolam PK profiles are assessed, samples will be collected and analyzed for circulating IL-6, inflammatory panel (collected at screening, baseline and pre-dose Day 1 only), total IL-17A (after following initiation of secukinumab treatment), hsCRP and for 4-beta-hydroxycholesterol (exploratory endogenous phenotyping marker of CYP3A activity). There will be an extended treatment period during which patients will receive secukinumab 300 mg s.c. at Weeks 8, 12, 16, 20 and 24. Then there will be a follow-up period of 12 weeks following the last dose administered at Week 24. Visits will be at Weeks 28, 32 and 36.