The study evaluated the efficacy of AMG 827 compared with placebo as measured by the percent of improvement in PASI score at week 12.

The study evaluated the efficacy of AMG 827 compared with placebo as measured by the percent of improvement in PASI score at week 12. Subjects were randomized ina 1:1:1:1:1 ratio. Subjects randomized to receive AMG 827 received 70, 140, or 210 mg at day 1 and weeks 4 and 8.

Inclusion Criteria:

• Subject has had stable moderate to severe plaque psoriasis for at least 6 months
• Subject has received at least one previous phototherapy or systemic psoriasis therapy or has been a candidate to receive phototherapy or systemic psoriasis therapy in the opinion of the investigator.
• Subject has involved BSA ≥ 10% and PASI ≥ 12 at screening and at baseline.

Exclusion Criteria:

• Subject diagnosed with erythrodermic psoriasis, pustular psoriasis, medication-induced, or medication-exacerbated psoriasis.
• Evidence of skin conditions at the time of the screening visit (eg, eczema, guttate psoriasis) that would interfere with evaluations of the effect of IP on psoriasis.
• Subject has any active CTCAE grade 2 or higher infection
• Subject has a significant concurrent medical condition or laboratory abnormalities, as defined in the study protocol.
• Subject has used the following therapies within 14 days of the first dose: UVB therapy or topical psoriasis therapies other than Class I or II topical steroids
• Subject has used the following therapies within 28 days of the first dose: Class I or II topical steroids, UVA therapy (with or without psoralen), or systemic psoriasis therapies
• Subject has used the following therapies within 3 months of the first dose: adalimumab, alefacept, etanercept, infliximab, certolizumab, or live vaccines
• Subject has used an anti-IL12/IL23 inhibitor within 6 months of the first dose
• Subject has previously used an anti-IL17 biologic therapy, efalizumab, or rituximab