Study of Efficacy, Safety, and Withdrawal and Retreatment With Brodalumab in Moderate to Severe Plaque Psoriasis Subjects (AMAGINE-1)

• Static Physician Global Assessment (sPGA) score [ Time Frame: 12 weeks ] [ Designated as safety issue: No ]
  Efficacy of brodalumab in subjects with moderate to severe plaque psoriasis
• Improvement in Psoriasis Area and Severity Index (PASI) [ Time Frame: 12 weeks ] [ Designated as safety issue: No ]
  Efficacy of brodalumab in subjects with moderate to severe plaque psoriasis

• Static Physician Global Assessment (sPGA) score [ Time Frame: 12 weeks and 52 weeks ] [ Designated as safety issue: No ]
  Efficacy of brodalumab in subjects with moderate to severe plaque psoriasis
• Improvement in Psoriasis Area and Severity Index (PASI) [ Time Frame: 12 weeks ] [ Designated as safety issue: No ]
  Efficacy of brodalumab in subjects with moderate to severe plaque psoriasis
• Patient reported outcomes. Symptom score [ Time Frame: 12 weeks ] [ Designated as safety issue: No ]
  Subject-reported outcomes assessment
• Subject incidence of adverse events [ Time Frame: 12 weeks and 5 years ] [ Designated as safety issue: Yes ]
  Safety profile of brodalumab
• Subject incidence of adverse events of interest [ Time Frame: 12 weeks and 5 years ] [ Designated as safety issue: Yes ]
  Safety profile of brodalumab
• Presence of anti-brodalumab antibodies [ Time Frame: 12 weeks and 5 years ] [ Designated as safety issue: Yes ]
  Safety profile of brodalumab

• Static Physician Global Assessment (sPGA) score [ Time Frame: 12 weeks and 52 weeks ] [ Designated as safety issue: No ]
  Efficacy of brodalumab in subjects with moderate to severe plaque psoriasis
• Improvement in Psoriasis Area and Severity Index (PASI) [ Time Frame: 12 weeks ] [ Designated as safety issue: No ]
  Efficacy of bradalumab in subjects with moderate to severe plaque psoriasis
• Patient reported outcomes. Symptom score [ Time Frame: 12 weeks ] [ Designated as safety issue: No ]
  Subject-reported outcomes assessment
• Subject incidence of adverse events [ Time Frame: 12 weeks and 5 years ] [ Designated as safety issue: Yes ]
  Safety profile of brodalumab
• Subject incidence of adverse events of interest [ Time Frame: 12 weeks and 5 years ] [ Designated as safety issue: Yes ]
  Safety profile of brodalumab
• Presence of anti-brodalumab antibodies [ Time Frame: 12 weeks and 5 years ] [ Designated as safety issue: Yes ]
  Safety profile of brodalumab

The purpose of this study is to assess the safety and efficacy of brodalumab taken every two weeks at two different doses in participants with moderate to severe plaque psoriasis.

A second purpose of this study is to assess the safety and efficacy when brodalumab is replaced with placebo in some participants compared with the participants who are still receiving the brodalumab.

• Drug: 210 mg brodalumab
  210 mg brodalumab administered subcutaneous (SC)
• Drug: 140 mg brodalumab
  140 mg brodalumab administered subcutaneous (SC)
• Drug: placebo
  Placebo administered subcutaneous (SC)

• Experimental: 210 mg brodalumab
  Administered by subcutaneous (SC) injection until week 12. At week 12, participants are rerandomized to placebo or continued treatment. Participants are retreated at return of disease.
  Interventions:

  • Drug: 210 mg brodalumab
  • Drug: placebo
• Experimental: 140 mg brodalumab
  Administered by subcutaneous (SC) injection until week 12. At week 12, participants are rerandomized to placebo or continued treatment. Participants are retreated at return of disease.
  Interventions:

  • Drug: 140 mg brodalumab
  • Drug: placebo
• Placebo Comparator: placebo
  Administered by SC injection until week 12. At week 12 particpants are assigned to 210 mg brodalumab.
  Interventions:

  • Drug: 210 mg brodalumab
  • Drug: placebo

Inclusion Criteria:

• Subject has had stable moderate to severe plaque psoriasis for at least 6 months
• Subject must be considered, in the opinion of the investigator, to be a suitable candidate for treatment with a biologic per regional labeling
• Subject has involved body surface area (BSA) ≥ 10%, PASI ≥ 12, and sPGA ≥ 3 at screening and at baseline

Exclusion Criteria:

• Subject diagnosed with erythrodermic psoriasis, pustular psoriasis, guttate psoriasis, medication-induced psoriasis, or other skin conditions at (eg, eczema) that would interfere with study evaluations
• Subject has known history of Crohn's disease
• Subject has any other significant concurrent medical condition or laboratory abnormalities, as defined in the study protocol
• Subject has stopped using certain psoriasis therapies as defined in the study protocol
• Subject has previously used any anti-IL-17 biologic therapy