A Study To Evaluate The Effects And Safety Of Treatment, Treatment Withdrawal, Followed By Re-Treatment With CP-690,550 In Subjects With Moderate To Severe Chronic Plaque Psoriasis

Study Overview
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Brief Summary
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The primary objectives of the study are to 1) compare the efficacy responses of CP 690,550 (5 mg BID and 10 mg BID) versus placebo following 24 weeks of CP 690,550 treatment and subsequent withdrawal of active treatment at various timepoints during the 16 week double blind active or placebo treatment period; 2) evaluate the regain of efficacy responses of CP 690,550 (5 mg BID and 10 mg BID) following 4 -16 weeks of CP 690,550 treatment withdrawal and subsequent re treatment; and 3) evaluate the safety and tolerability of CP 690,550 (5 mg BID and 10 mg BID) in subjects with moderate to severe chronic plaque psoriasis who are candidates for systemic therapy or phototherapy.

Official Title
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A Phase 3, Multi-Site, Randomized, Mixed-Blind, Parallel-Group Treatment Withdrawal And Re-Treatment Study Of The Efficacy And Safety Of 2 Oral Doses Of CP-690,550 In Subjects With Moderate To Severe Chronic Plaque Psoriasis

Conditions
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Psoriasis

Intervention / Treatment
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* Drug: CP-690,550
* Drug: CP-690,550
* Drug: CP-690,550
* Drug: CP-690,550


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: 18 years or older with diagnosis of plaque-type psoriasis (psoriasis vulgaris) for at least 12 months prior to first dose of study drug; Psoriasis Area and Severity Index (PASI) score of 12 or greater, AND Physician's Global Assessment (PGA) score of 3 (moderate) or 4 (severe); Psoriasis covering at least 10% of body surface area; No evidence of active or latent or inadequately treated infection with Tuberculosis or other serious infections. Exclusion Criteria: Non-plaque or drug induced forms of psoriasis; Cannot discontinue current oral, injectable or topical therapy for psoriasis or cannot discontinue phototherapy (Psoralen Ultraviolet A; Ultraviolet B). Any uncontrolled significant medical condition.

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Quadruple


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Active Treatment (10 mg) BID / Placebo BID<br>Continuous active treatment (CP-690,550) for 24 weeks, followed by treatment withdrawal (placebo treatment) for 4-16 weeks, followed by active treatment (CP-690,550) for 16-28 weeks | Drug: CP-690,550<br>* 10 mg of CP-690,550 oral BID or placebo oral BID, as appropriate based on treatment withdrawal/retreatment design<br>|
| Experimental: Active Treatment (10 mg) BID<br>Continuous active treatment (CP-690,550) for 56 weeks | Drug: CP-690,550<br>* 10 mg oral BID<br>|
| Experimental: Active Treatment (5 mg) BID / Placebo BID<br>Continuous active treatment (CP-690,550) for 24 weeks, followed by treatment withdrawal (placebo treatment) for 4-16 weeks, followed by active treatment (CP-690,550) for 16-28 weeks | Drug: CP-690,550<br>* 5 mg of CP-690,550 oral BID or Placebo oral BID, as appropriate based on treatment withdrawal/retreatment design<br>|
| Experimental: Active Treatment (5 mg) BID<br>Continuous active treatment (CP-690,550) for 56 weeks | Drug: CP-690,550<br>* 5 mg oral BID<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Percentage of Participants Maintaining a Psoriasis Area and Severity Index 75 (PASI75) Response During the Double-Blind Treatment Withdrawal Period (Period B) | The PASI quantifies the severity of a participant's psoriasis based on both lesion severity and the percent of body surface area (BSA) affected. PASI is a composite scoring by the investigator of degree of erythema, induration, and scaling (each scored separately) for each of 4 body regions (head and neck, upper limbs, trunk [including axillae and groin], and lower limbs [including buttocks), with adjustment for the percent of BSA involved for each body region and for the proportion of the body region to the whole body. The PASI score can vary in increments of 0.1 and range from 0.0 to 72.0, with higher scores representing greater severity of psoriasis. PASI75 response defined as at least a 75 percent (%) reduction in PASI relative to baseline. | Weeks 4, 8 12, and 16 (Period B) | 
| Percentage of Participants Maintaining a Physician's Global Assessment (PGA) Response During the Double-Blind Treatment Withdrawal (Period B) | The PGA of psoriasis is scored on a 5-point scale, reflecting a global consideration of the erythema, induration, and scaling across all psoriatic lesions. Average erythema, induration, and scaling are scored separately over the whole body according to a 5-point severity scale (0=clear; 1=almost clear; 2=mild; 3=moderate; and 4=severe). PGA response defined as 0 (clear) or 1 (almost clear). | Weeks 4, 8, 12, and 16 (Period B) | 
| Percentage of Participants Achieving a PASI75 Response During CP-690,550 Re-Treatment (Period C) Among Those Who Had a Greater Than (>)50% Reduction of Visit A4/Week 24 PASI Response During Double-Blind Treatment Withdrawal (Period B) | The PASI quantifies the severity of a participant's psoriasis based on both lesion severity and the percent of BSA affected. PASI is a composite scoring by the investigator of degree of erythema, induration, and scaling (each scored separately) for each of 4 body regions (head and neck, upper limbs, trunk [including axillae and groin], and lower limbs [including buttocks), with adjustment for the percent of BSA involved for each body region and for the proportion of the body region to the whole body. PASI75 response is defined as at least 75% reduction in PASI relative to Baseline/Day 1. Baseline defined as the last observation up to first dosing date in Period C. PASI responses at each period were relative to Baseline-A, where Baseline-A was defined as the last observation up to first dosing date in Period A. | Baseline and Weeks 4, 8, and 16 (Period C) | 
| Percentage of Participants Achieving a PGA Response of Clear or Almost Clear During CP-690,550 Re-treatment (Period C) Among Participants Who Had a PGA of Mild, Moderate, or Severe During Double-Blind Treatment Withdrawal (Period B) | The PGA of psoriasis is scored on a 5-point scale, reflecting a global consideration of the erythema, induration, and scaling across all psoriatic lesions. Average erythema, induration, and scaling are scored separately over the whole body according to a 5-point severity scale (0=clear; 1=almost clear; 2=mild; 3=moderate; and 4=severe). | Baseline and Weeks 4, 8, and 16 (Period C) | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Median Time to PASI75 Response During Initial CP-690,550 Treatment (Period A) | The PASI quantifies the severity of a participant's psoriasis based on both lesion severity and the percent of BSA affected. PASI is a composite scoring by the investigator of degree of erythema, induration, and scaling (each scored separately) for each of 4 body regions (head and neck, upper limbs, trunk [including axillae and groin], and lower limbs [including buttocks), with adjustment for the percent of BSA involved for each body region and for the proportion of the body region to the whole body. PASI75 response defined as 75% reduction in PASI relative to baseline. | Weeks 4, 8, 16, and 24 (Period A) | 
| Median Time to PGA Response of Clear or Almost Clear During Initial CP-690,550 Treatment (Period A) | The PGA of psoriasis is scored on a 5-point scale, reflecting a global consideration of the erythema, induration, and scaling across all psoriatic lesions. Average erythema, induration, and scaling are scored separately over the whole body according to a 5-point severity scale (0=clear; 1=almost clear; 2=mild; 3=moderate; and 4=severe). PGA response defined as 0 (clear) or 1 (almost clear). | Weeks 4, 8, 16, and 24 (Period A) | 
| Percentage of Participants Achieving Both a PASI50-75 Response and Dermatology Life Quality Index (DLQI) ≤5 Response During Initial CP-690,550 Treatment (Period A) | PASI50-75 response defined as a reduction of at least 50% but less than 75%. The DLQI is a general dermatology questionnaire that consists of 10 items that assess participant health related quality of life (daily activities, personal relationships, symptoms and feelings, leisure, work and school, and treatment. The minimally important difference for the DLQI has been estimated as a 2 to 5 point change from baseline. | Weeks 4, 8, 16, and 24 (Period A) | 
| Percentage of Participant Maintaining an Adequate Response During the Double-Blind Treatment Withdrawal (Period B) | Adequate response defined as >50% reduction of the Visit A4/Week 24 (last visit in Period A) PASI response. | Weeks 4, 8, 12, and 16 (Period B) | 
| Median Time to Loss of Adequate Response During the Double-Blind Treatment Withdrawal (Period B) | Adequate response defined as >50% reduction of the Visit A4/Week 24 (last visit in Period A) PASI response. | Weeks 4, 8, 12, and 16 (Period B) | 
| Percentage of Participants With PASI Score ≥125% of Baseline-A or New Type of Psoriasis (Pustular, Erythrodermic) During the Period Between Week 24 and Week 32 (Period B) | The PASI score can vary in increments of 0.1 and range from 0.0 to 72.0, with higher scores representing greater severity of psoriasis. PASI responses at each period are relative to Baseline-A where Baseline-A was defined as the last observation up to first dosing date in Period A. Weeks 4 and 8 are relative to the Period B baseline and are the same as Weeks 28 and 32, which are relative to Period A baseline. 95% confidence interval is constructed using the normal approximation to the binomial distribution of two-sample proportion. | Weeks 4 and 8 (Period B) | 
| Percentage of Participants With PASI Score ≥125% of Baseline-A or New Type of Psoriasis (Pustular, Erythrodermic) During the Double-Blind Treatment Withdrawal (Period B) | The PASI score can vary in increments of 0.1 and range from 0.0 to 72.0, with higher scores representing greater severity of psoriasis. PASI responses at each period are relative to Baseline-A where Baseline-A was defined as the last observation up to first dosing date in Period A. 95% confidence interval is constructed using the normal approximation to the binomial distribution of two-sample proportion. | Weeks 4, 8, 12, and 16 (Period B) | 
| Percentage of Participants Maintaining Adequate PASI Response and Maintaining PGA Response (Clear or Almost Clear) During the Double-Blind Treatment Withdrawal (Period B) | Adequate PASI response defined as less than or equal to 50% reduction of the Visit A4/Week 24 PASI Response. | Week 24 (Period A) and Weeks 4, 8, 12, and 16 (Period B) | 
| Median Time to Loss of >50% of the Visit A4/Week 24 PASI Response and Loss of PGA Response (Clear or Almost Clear) During the Double-Blind Treatment Withdrawal (Period B) |  | Week 24 (Period A) and Weeks 4, 8, 12, and 16 (Period B) | 
| Percentage of Participants Regaining PASI75 and PGA Response (Clear or Almost Clear) During CP-690,550 Re-Treatment (Period C) Among Participants Who Lost Both PASI75 Response and PGA Response (Clear or Almost Clear) at the Beginning of Period C | PASI75 response defined as at least a 75% reduction in PASI relative to baseline. | Weeks 4, 8, and 16 (Period C) | 
| Median Time to Regain PASI75 and PGA Response (Clear or Almost Clear) During CP-690,550 Re-Treatment (Period C) Among Participants Who Lost Both PASI75 Response and PGA Response (Clear or Almost Clear) at the Beginning of Period C | PASI75 response defined as at least a 75% reduction in PASI relative to baseline. | Weeks 4, 8, and 16 (Period C) | 
| Percentage of Participants Regaining PASI75 and PGA Response (PGA of Clear or Almost Clear) During CP-690,550 Re-Treatment (Period C) Who Had Lost Both PASI75 Response and PGA Response at the Beginning of Period C | PASI75 response defined as at least a 75% reduction in PASI relative to baseline. PASI responses at each period are relative to Baseline-A, where Baseline-A is defined as the last observation up to first dosing date in Period A. 95% confidence interval constructed using the normal approximation to the binomial distribution of one-sample proportion. | Baseline and Weeks 4, 8, and 16 (Period C) | 
| Median Time to PASI75 Response During CP-690,550 Re-Treatment (Period C) For Those Who Had a >50% Reduction of Visit A4/Week 24 PASI Response During Double-Blind Treatment Withdrawal (Period B) | PASI75 response defined as at least a 75% reduction in PASI relative to baseline. | Baseline and Weeks 4, 8, and 16 (Period C) | 
| Median Time to PGA Response of Clear or Almost Clear During CP-690,550 Re-Treatment (Period C) Among Participants Who Had a PGA of Mild, Moderate, or Severe at the Beginning of Period C |  | Baseline and Weeks 4, 8, and 16 (Period C) | 
| Percentage of Participants With a PASI75 Response During the Initial CP-690,550 Treatment (Period A) | PASI75 response defined as at least a 75% reduction in PASI relative to baseline. Baseline defined as the last observation up to the first dosing date in Period A. 95% confidence interval is constructed using the normal approximation to the binomial distribution of one-sample proportion. | Weeks 4, 8, 16, and 24 (Period A) | 
| Percentage of Participants With a PASI75 Response During Double-Blind Withdrawal Treatment (Period B) | PASI75 response defined as at least a 75% reduction in PASI relative to baseline. PASI responses in each period are relative to Baseline-A, where Baseline-A is defined as the last observation until first dosing date in Period A. 95% confidence interval is constructed using the normal approximation to the binomial distribution of one-sample proportion. | Weeks 4, 8, 12, and 16 (Period B) | 
| Percentage of Participants With a PASI75 Response During the CP-690,550 Re-Treatment (Period C) | PASI75 response defined as at least a 75% reduction in PASI relative to baseline. PASI responses in each period are relative to Baseline-A, where Baseline-A is defined as the last observation until first dosing date in Period A. 95% confidence interval is constructed using the normal approximation to the binomial distribution of one-sample proportion. | Weeks 4, 8, and 16 (Period C) | 
| Percentage of Participants With PGA Response of Clear or Almost Clear During the Initial CP-690,550 Treatment (Period A) | PGA response was defined as 0 (clear) or 1 (almost clear) on a 5-point scale where 0=clear; 1=almost clear; 2=mild; 3=moderate; and 4=severe. 95% confidence interval is constructed using the normal approximation to the binomial distribution of one-sample proportion. | Weeks 4, 8, 16, and 24 (Period A) | 
| Percentage of Participants With PGA Response of Clear or Almost Clear During Double-Blind Withdrawal Treatment (Period B) | PGA response was defined as 0 (clear) or 1 (almost clear) on a 5-point scale where 0=clear; 1=almost clear; 2=mild; 3=moderate; and 4=severe. 95% confidence interval is constructed using the normal approximation to the binomial distribution of two-sample proportion. | Weeks 4, 8, 12, and 16 (Period B) | 
| Percentage of Participants With PGA Response of Clear or Almost Clear During the CP-690,550 Re-Treatment (Period C) | PGA response was defined as 0 (clear) or 1 (almost clear) on a 5-point scale where 0=clear; 1=almost clear; 2=mild; 3=moderate; and 4=severe. 95% confidence interval is constructed using the normal approximation to the binomial distribution of one-sample proportion. | Weeks 4, 8, and 16 (Period C) | 
| Mean Total Percent of Psoriatic Body Surface Area (BSA) During Initial CP-690,550 Treatment (Period A) | Assessment of BSA with psoriasis performed separately for 4 body regions: head and neck, upper limbs, trunk (including axillae and groin), and lower limbs (including buttocks). The %surface area with psoriasis was estimated by means of the handprint method, where the full palmar hand of the participant (fully extended palm, fingers and thumb together) represented approximately 1% of the total BSA. The number of handprints of psoriatic skin in a body region was used to determine the extent (%) to which a body region was involved with psoriasis. | Baseline and Weeks 4, 8, 16, and 24 (Period A) | 
| Mean Total Percent of Psoriatic BSA During Double-Blind Treatment Withdrawal (Period B) | Assessment of BSA with psoriasis performed separately for 4 body regions: head and neck, upper limbs, trunk (including axillae and groin), and lower limbs (including buttocks). The %surface area with psoriasis was estimated by means of the handprint method, where the full palmar hand of the participant (fully extended palm, fingers and thumb together) represented approximately 1% of the total BSA. The number of handprints of psoriatic skin in a body region was used to determine the extent (%) to which a body region was involved with psoriasis. | Baseline and Weeks 4, 8, 12, and 16 (Period B) | 
| Mean Total Percent of Psoriatic BSA During CP-690,550 Re-Treatment (Period C) | Assessment of BSA with psoriasis performed separately for 4 body regions: head and neck, upper limbs, trunk (including axillae and groin), and lower limbs (including buttocks). The %surface area with psoriasis was estimated by means of the handprint method, where the full palmar hand of the participant (fully extended palm, fingers and thumb together) represented approximately 1% of the total BSA. The number of handprints of psoriatic skin in a body region was used to determine the extent (%) to which a body region was involved with psoriasis. | Baseline and Weeks 4, 8, and 16 (Period C) | 
| Mean Change From Baseline in Total Percent of Psoriatic BSA During Initial CP-690,550 Treatment (Period A) | Baseline defined as the last observation up to first dosing date in Period A. | Weeks 4, 8, 16, and 24 (Period A) | 
| Mean Change From Baseline in Total Percent of Psoriatic BSA During Double-Blind Treatment Withdrawal (Period B) | Baseline defined as the last observation up to first dosing date in Period B. | Weeks 4, 8, 12, and 16 (Period B) | 
| Mean Change From Baseline in Total Percent of Psoriatic BSA During CP-690,550 Re-Treatment (Period C) | Baseline was defined as the last observation until first dosing date in Period C. | Weeks 4, 8, and 16 (Period C) | 
| Mean Percent of Psoriatic BSA by Body Region During Initial CP-690,550 Treatment (Period A) | Assessment of BSA with psoriasis performed separately for 4 body regions: head and neck, upper limbs, trunk (including axillae and groin), and lower limbs (including buttocks). The %surface area with psoriasis was estimated by means of the handprint method, where the full palmar hand of the participant (fully extended palm, fingers and thumb together) represented approximately 1% of the total BSA. The number of handprints of psoriatic skin in a body region was used to determine the extent (%) to which a body region was involved with psoriasis. | Baseline and Weeks 4, 8, 16, and 24 (Period A) | 
| Mean Percent of Psoriatic BSA by Body Region During Double-Blind Treatment Withdrawal (Period B) | Assessment of BSA with psoriasis performed separately for 4 body regions: head and neck, upper limbs, trunk (including axillae and groin), and lower limbs (including buttocks). The %surface area with psoriasis was estimated by means of the handprint method, where the full palmar hand of the participant (fully extended palm, fingers and thumb together) represented approximately 1% of the total BSA. The number of handprints of psoriatic skin in a body region was used to determine the extent (%) to which a body region was involved with psoriasis. | Baseline and Weeks 4, 8, 12, and 16 (Period B) | 
| Mean Percent of Psoriatic BSA by Body Region During CP-690,550 Re-Treatment (Period C) | Assessment of BSA with psoriasis performed separately for 4 body regions: head and neck, upper limbs, trunk (including axillae and groin), and lower limbs (including buttocks). The %surface area with psoriasis was estimated by means of the handprint method, where the full palmar hand of the participant (fully extended palm, fingers and thumb together) represented approximately 1% of the total BSA. The number of handprints of psoriatic skin in a body region was used to determine the extent (%) to which a body region was involved with psoriasis. | Baseline and Weeks 4, 8, and 16 (Period C) | 
| Mean Change From Baseline in Percent of Psoriatic BSA by Body Region During Initial CP-690,550 Treatment (Period A) | Baseline defined as the last observation up to first dosing date in Period A. | Weeks 4, 8, 16, and 24 (Period A) | 
| Mean Change From Baseline in Percent of Psoriatic BSA by Body Region During Double-Blind Treatment Withdrawal (Period B) | Baseline defined as the last observation up to first dosing date in Period B. | Weeks 4, 8, 12, and 16 (Period B) | 
| Mean Change From Baseline in Percent of Psoriatic BSA by Body Region During CP-690,550 Re-Treatment (Period C) | Baseline defined as the last observation up to first dosing date in Period C. | Weeks 4, 8, and 16 (Period C) | 
| Mean PASI Score During Initial CP-690,550 Treatment (Period A) | Combined assessment of lesion severity and area affected into single score; range=0(no disease)-72(maximal disease). Body divided into 4 sections=head, upper/lower limbs, trunk; each area scored by itself and scores combined for final PASI. For each section percent area of skin involved was estimated:0(0%)-6(90-100%) and severity estimated by clinical signs of erythema, induration, scaling; ranged 0-4: 0=none, 1=slight, 2=moderate, 3=marked, 4=very marked. Final PASI=sum of severity parameters for each section*area score*weighing factor (head=0.1, upper limbs=0.2, trunk=0.3, lower limbs=0.4). PASI score can vary in increments of 0.1; higher scores represent greater severity of psoriasis. | Baseline and Weeks 4, 8, 16, and 24 (Period A) | 
| Mean PASI Score During Double-Blind Treatment Withdrawal (Period B) | Combined assessment of lesion severity and area affected into single score; range=0(no disease)-72(maximal disease). Body divided into 4 sections=head, upper/lower limbs, trunk; each area scored by itself and scores combined for final PASI. For each section percent area of skin involved was estimated:0(0%)-6(90-100%) and severity estimated by clinical signs of erythema, induration, scaling; ranged 0-4: 0=none, 1=slight, 2=moderate, 3=marked, 4=very marked. Final PASI=sum of severity parameters for each section*area score*weighing factor (head=0.1, upper limbs=0.2, trunk=0.3, lower limbs=0.4). PASI score can vary in increments of 0.1; higher scores represent greater severity of psoriasis. Baseline defined as last observation up to first dosing date in Period B. | Baseline and Weeks 4, 8, 12, and 16 (Period B) | 
| Mean PASI Score During the CP-690,550 Re-Treatment (Period C) | Combined assessment of lesion severity and area affected into single score; range=0(no disease)-72(maximal disease). Body divided into 4 sections=head, upper/lower limbs, trunk; each area scored by itself and scores combined for final PASI. For each section percent area of skin involved was estimated:0(0%)-6(90-100%) and severity estimated by clinical signs of erythema, induration, scaling; ranged 0-4: 0=none, 1=slight, 2=moderate, 3=marked, 4=very marked. Final PASI=sum of severity parameters for each section*area score*weighing factor (head=0.1, upper limbs=0.2, trunk=0.3, lower limbs=0.4). PASI score can vary in increments of 0.1; higher scores represent greater severity of psoriasis. Baseline defined as last observation up to first dosing date in Period C. | Baseline and Weeks 4, 8, and 16 (Period C) | 
| Mean Change From Baseline-A in PASI Score During Initial CP-690,550 Treatment (Period A) | Combined assessment of lesion severity and area affected into single score; range=0(no disease)-72(maximal disease). Body divided into 4 sections=head, upper/lower limbs, trunk; each area scored by itself and scores combined for final PASI. For each section percent area of skin involved was estimated:0(0%)-6(90-100%) and severity estimated by clinical signs of erythema, induration, scaling; ranged 0-4: 0=none, 1=slight, 2=moderate, 3=marked, 4=very marked. Final PASI=sum of severity parameters for each section*area score*weighing factor (head=0.1, upper limbs=0.2, trunk=0.3, lower limbs=0.4). PASI score can vary in increments of 0.1; higher scores represent greater severity of psoriasis. Baseline-A defined as last observation up to first dosing date in Period A. | Weeks 4, 8, 16, and 24 (Period A) | 
| Mean Change From Baseline-B in PASI Score During Double-Blind Treatment Withdrawal (Period B) | Combined assessment of lesion severity and area affected into single score; range=0(no disease)-72(maximal disease). Body divided into 4 sections=head, upper/lower limbs, trunk; each area scored by itself and scores combined for final PASI. For each section percent area of skin involved was estimated:0(0%)-6(90-100%) and severity estimated by clinical signs of erythema, induration, scaling; ranged 0-4: 0=none, 1=slight, 2=moderate, 3=marked, 4=very marked. Final PASI=sum of severity parameters for each section*area score*weighing factor (head=0.1, upper limbs=0.2, trunk=0.3, lower limbs=0.4). PASI score can vary in increments of 0.1; higher scores represent greater severity of psoriasis. Baseline-B defined as last observation up to first dosing date in Period B. | Weeks 4, 8, 12, and 16 (Period B) | 
| Mean Change From Baseline-C in PASI Score During the CP-690,550 Re-Treatment (Period C) | Combined assessment of lesion severity and area affected into single score; range=0(no disease)-72(maximal disease). Body divided into 4 sections=head, upper/lower limbs, trunk; each area scored by itself and scores combined for final PASI. For each section percent area of skin involved was estimated:0(0%)-6(90-100%) and severity estimated by clinical signs of erythema, induration, scaling; ranged 0-4: 0=none, 1=slight, 2=moderate, 3=marked, 4=very marked. Final PASI=sum of severity parameters for each section*area score*weighing factor (head=0.1, upper limbs=0.2, trunk=0.3, lower limbs=0.4). PASI score can vary in increments of 0.1; higher scores represent greater severity of psoriasis. Baseline-C defined as last observation up to first dosing date in Period C. | Weeks 4, 8, and 16 (Period C) | 
| Mean PASI Component Scores During Initial CP-690,550 Treatment (Period A) | Combined assessment of lesion severity and area affected into single score; range=0(no disease)-72(maximal disease). Body divided into 4 sections=head, upper/lower limbs, trunk; each area scored by itself and scores combined for final PASI. For each section percent area of skin involved was estimated:0(0%)-6(90-100%) and severity estimated by clinical signs of erythema, induration, scaling; ranged 0-4: 0=none, 1=slight, 2=moderate, 3=marked, 4=very marked. Final PASI=sum of severity parameters for each section*area score*weighing factor (head=0.1, upper limbs=0.2, trunk=0.3, lower limbs=0.4). PASI score can vary in increments of 0.1; higher scores represent greater severity of psoriasis. Baseline defined as last observation up to first dosing date in Period B. | Baseline and Weeks 4, 8, 16, and 24 (Period A) | 
| Mean PASI Component Scores During Double-Blind Treatment Withdrawal (Period B) | Combined assessment of lesion severity and area affected into single score; range=0(no disease)-72(maximal disease). Body divided into 4 sections=head, upper/lower limbs, trunk; each area scored by itself and scores combined for final PASI. For each section percent area of skin involved was estimated:0(0%)-6(90-100%) and severity estimated by clinical signs of erythema, induration, scaling; ranged 0-4: 0=none, 1=slight, 2=moderate, 3=marked, 4=very marked. Final PASI=sum of severity parameters for each section*area score*weighing factor (head=0.1, upper limbs=0.2, trunk=0.3, lower limbs=0.4). PASI score can vary in increments of 0.1; higher scores represent greater severity of psoriasis. Baseline defined as last observation up to first dosing date in Period B. | Baseline and Weeks 4, 8, 12, and 16 (Period B) | 
| Mean PASI Component Scores During the CP-690,550 Re-Treatment (Period C) | Combined assessment of lesion severity and area affected into single score; range=0(no disease)-72(maximal disease). Body divided into 4 sections=head, upper/lower limbs, trunk; each area scored by itself and scores combined for final PASI. For each section percent area of skin involved was estimated:0(0%)-6(90-100%) and severity estimated by clinical signs of erythema, induration, scaling; ranged 0-4: 0=none, 1=slight, 2=moderate, 3=marked, 4=very marked. Final PASI=sum of severity parameters for each section*area score*weighing factor (head=0.1, upper limbs=0.2, trunk=0.3, lower limbs=0.4). PASI score can vary in increments of 0.1; higher scores represent greater severity of psoriasis. Baseline defined as last observation up to first dosing date in Period C. | Baseline and Weeks 4, 8, and 16 (Period C) | 
| Mean Change From Baseline in PASI Component Scores During Initial CP-690,550 Treatment (Period A) | Combined assessment of lesion severity and area affected into single score; range=0(no disease)-72(maximal disease). Body divided into 4 sections=head, upper/lower limbs, trunk; each area scored by itself and scores combined for final PASI. For each section percent area of skin involved was estimated:0(0%)-6(90-100%) and severity estimated by clinical signs of erythema, induration, scaling; ranged 0-4: 0=none, 1=slight, 2=moderate, 3=marked, 4=very marked. Final PASI=sum of severity parameters for each section*area score*weighing factor (head=0.1, upper limbs=0.2, trunk=0.3, lower limbs=0.4). PASI score can vary in increments of 0.1; higher scores represent greater severity of psoriasis. Baseline defined as last observation up to first dosing date in Period B. | Weeks 4, 8, 16, and 24 (Period A) | 
| Mean Change From Baseline in PASI Component Scores During Double-Blind Treatment Withdrawal (Period B) | Combined assessment of lesion severity and area affected into single score; range=0(no disease)-72(maximal disease). Body divided into 4 sections=head, upper/lower limbs, trunk; each area scored by itself and scores combined for final PASI. For each section percent area of skin involved was estimated:0(0%)-6(90-100%) and severity estimated by clinical signs of erythema, induration, scaling; ranged 0-4: 0=none, 1=slight, 2=moderate, 3=marked, 4=very marked. Final PASI=sum of severity parameters for each section*area score*weighing factor (head=0.1, upper limbs=0.2, trunk=0.3, lower limbs=0.4). PASI score can vary in increments of 0.1; higher scores represent greater severity of psoriasis. Baseline defined as last observation up to first dosing date in Period B. | Weeks 4, 8, 12, and 16 (Period B) | 
| Mean Change From Baseline in PASI Component Scores During the CP-690,550 Re-Treatment (Period C) | Combined assessment of lesion severity and area affected into single score; range=0(no disease)-72(maximal disease). Body divided into 4 sections=head, upper/lower limbs, trunk; each area scored by itself and scores combined for final PASI. For each section percent area of skin involved was estimated:0(0%)-6(90-100%) and severity estimated by clinical signs of erythema, induration, scaling; ranged 0-4: 0=none, 1=slight, 2=moderate, 3=marked, 4=very marked. Final PASI=sum of severity parameters for each section*area score*weighing factor (head=0.1, upper limbs=0.2, trunk=0.3, lower limbs=0.4). PASI score can vary in increments of 0.1; higher scores represent greater severity of psoriasis. Baseline defined as last observation up to first dosing date in Period C. | Weeks 4, 8, and 16 (Period C) | 
| Percentage of Participants Achieving at Least a 50% Reduction in PASI Relative to Baseline-A (PASI50) During Period A | PASI quantifies the severity of psoriasis based on both lesion severity and the percent of BSA) affected. PASI is a composite score by the investigator of degree of erythema, induration, and scaling (scored separately) for each of 4 body regions (head and neck, upper limbs, trunk, and lower limbs), with adjustment for percent of BSA involved for each body region and for proportion of the body region to the whole body. PASI score can vary in increments of 0.1 and range from 0.0 to 72.0, with higher scores representing greater severity of psoriasis. | Weeks 4, 8, 16, and 24 (Period A) | 
| Percentage of Participants Achieving at Least a 90% Reduction in PASI Relative to Baseline-A (PASI90) During Period A | PASI quantifies the severity of psoriasis based on both lesion severity and the percent of BSA) affected. PASI is a composite score by the investigator of degree of erythema, induration, and scaling (scored separately) for each of 4 body regions (head and neck, upper limbs, trunk, and lower limbs), with adjustment for percent of BSA involved for each body region and for proportion of the body region to the whole body. PASI score can vary in increments of 0.1 and range from 0.0 to 72.0, with higher scores representing greater severity of psoriasis. | Weeks 4, 8, 16, and 24 (Period A) | 
| Percentage of Participants Achieving at Least a 100% Reduction in PASI Relative to Baseline-A (PASI100) During Period A | PASI quantifies the severity of psoriasis based on both lesion severity and the percent of BSA) affected. PASI is a composite score by the investigator of degree of erythema, induration, and scaling (scored separately) for each of 4 body regions (head and neck, upper limbs, trunk, and lower limbs), with adjustment for percent of BSA involved for each body region and for proportion of the body region to the whole body. PASI score can vary in increments of 0.1 and range from 0.0 to 72.0, with higher scores representing greater severity of psoriasis. | Weeks 4, 8, 16, and 24 (Period A) | 
| Percentage of Participants Achieving at Least a 50% Reduction in PASI Relative to Baseline-A (PASI50) During the CP-690,550 Re-Treatment (Period C) | PASI quantifies severity of psoriasis based on both lesion severity and percent of BSA affected. PASI is a composite score by investigator of degree of erythema, induration, and scaling (scored separately) for each of 4 body regions (head/neck, upper limbs, trunk, lower limbs), with adjustment for percent of BSA involved for each body region and for proportion of body region to the whole body. PASI score can vary in increments of 0.1 and range from 0.0-72.0; higher scores representing greater severity of psoriasis. Baseline-A defined as last observation up to first dosing date in Period A. | Baseline and Weeks 4, 8, and 16 (Period C) | 
| Percentage of Participants Achieving at Least a 90% Reduction in PASI Relative to Baseline-A (PASI90) During the CP-690,550 Re-Treatment (Period C) | PASI quantifies severity of psoriasis based on both lesion severity and percent of BSA affected. PASI is a composite score by investigator of degree of erythema, induration, and scaling (scored separately) for each of 4 body regions (head/neck, upper limbs, trunk, lower limbs), with adjustment for percent of BSA involved for each body region and for proportion of body region to the whole body. PASI score can vary in increments of 0.1 and range from 0.0-72.0; higher scores representing greater severity of psoriasis. Baseline-A defined as last observation up to first dosing date in Period A. | Baseline and Weeks 4, 8, and 16 (Period C) | 
| Percentage of Participants Achieving 100% Reduction in PASI Relative to Baseline-A (PASI100) During the CP-690,550 Re-Treatment (Period C) | PASI quantifies severity of psoriasis based on both lesion severity and percent of BSA affected. PASI is a composite score by investigator of degree of erythema, induration, and scaling (scored separately) for each of 4 body regions (head/neck, upper limbs, trunk, lower limbs), with adjustment for percent of BSA involved for each body region and for proportion of body region to the whole body. PASI score can vary in increments of 0.1 and range from 0.0-72.0; higher scores representing greater severity of psoriasis. Baseline-A defined as last observation up to first dosing date in Period A. | Baseline and Weeks 4, 8, and 16 (Period C) | 
| Percentage of Participants With a PASI Score ≥125% of the Baseline-A PASI Score During Initial CP-690,550 Treatment (Period A) | PASI quantifies the severity of psoriasis based on both lesion severity and percent of BSA affected. PASI is a composite score by the investigator of degree of erythema, induration, and scaling (scored separately) for each of 4 body regions (head and neck, upper limbs, trunk, and lower limbs), with adjustment for the percent of BSA involved for each body region and for the proportion of the body region to the whole body. The PASI score can vary in increments of 0.1 and range from 0.0-72.0; higher scores representing greater severity of psoriasis. | Weeks 4, 8, 16, and 24 (Period A) | 
| Percentage of Participants With a PASI Score ≥125% of the Baseline-A PASI Score During Double-Blind Treatment Withdrawal (Period B) | PASI quantifies severity of psoriasis based on both lesion severity and percent of BSA affected. PASI is a composite score by investigator of degree of erythema, induration, and scaling (scored separately) for each of 4 body regions (head/neck, upper limbs, trunk, lower limbs), with adjustment for percent of BSA involved for each body region and for proportion of body region to the whole body. PASI score can vary in increments of 0.1 and range from 0.0-72.0; higher scores representing greater severity of psoriasis. Baseline-A defined as last observation up to first dosing date in Period A. | Weeks 4, 8, 12, and 16 (Period B) | 
| Percentage of Participants With a PASI Score ≥125% of the Baseline-A PASI Score During the CP-690,550 Re-Treatment (Period C) | PASI quantifies severity of psoriasis based on both lesion severity and percent of BSA affected. PASI is a composite score by investigator of degree of erythema, induration, and scaling (scored separately) for each of 4 body regions (head/neck, upper limbs, trunk, lower limbs), with adjustment for percent of BSA involved for each body region and for proportion of body region to the whole body. PASI score can vary in increments of 0.1 and range from 0.0-72.0; higher scores representing greater severity of psoriasis. Baseline-A defined as last observation up to first dosing date in Period A. | Weeks 4, 8, and 16 (Period C) | 
| Mean Itch Severity Item (ISI) Score During the Initial CP-690,550 Treatment (Period A) | The severity of itch (pruritus) due to psoriasis was assessed using the ISI, a single item, horizontal numeric rating scale. Participants were asked to rate your worst itching due to psoriasis over the past 24 hours on a numeric rating scale anchored by the terms No itching (0) and Worst possible itching (10) at the ends. | Baseline and Weeks 4, 8, 16, and 24 (Period A) | 
| Mean ISI Score During the Double-Blind Treatment Withdrawal (Period B) | The severity of itch (pruritus) due to psoriasis was assessed using the ISI, a single item, horizontal numeric rating scale. Participants were asked to rate your worst itching due to psoriasis over the past 24 hours on a numeric rating scale anchored by the terms No itching (0) and Worst possible itching (10) at the ends. | Baseline and Weeks 4, 8, 12, and 16 (Period B) | 
| Mean ISI Score During the CP-690,550 Re-Treatment (Period C) | The severity of itch (pruritus) due to psoriasis was assessed using the ISI, a single item, horizontal numeric rating scale. Participants were asked to rate your worst itching due to psoriasis over the past 24 hours on a numeric rating scale anchored by the terms No itching (0) and Worst possible itching (10) at the ends. | Baseline and Weeks 4, 8, and 16 (Period C) | 
| Mean Change From Baseline-A in ISI Score During the Initial CP-690,550 Treatment (Period A) | The severity of itch (pruritus) due to psoriasis was assessed using the ISI, a single item, horizontal numeric rating scale. Participants were asked to rate your worst itching due to psoriasis over the past 24 hours on a numeric rating scale anchored by the terms No itching (0) and Worst possible itching (10) at the ends. Baseline-A defined as the last observation up to first dosing date in Period A. | Weeks 4, 8, 16, and 24 (Period A) | 
| Mean Change From Baseline-B in ISI Score During the Double-Blind Treatment Withdrawal (Period B) | The severity of itch (pruritus) due to psoriasis was assessed using the ISI, a single item, horizontal numeric rating scale. Participants were asked to rate your worst itching due to psoriasis over the past 24 hours on a numeric rating scale anchored by the terms No itching (0) and Worst possible itching (10) at the ends. Baseline-B defined as the last observation up to first dosing date in Period B. | Weeks 4, 8, 12, and 16 (Period B) | 
| Mean Change From Baseline-C in ISI Score During the CP-690,550 Re-Treatment (Period C) | The severity of itch (pruritus) due to psoriasis was assessed using the ISI, a single item, horizontal numeric rating scale. Participants were asked to rate your worst itching due to psoriasis over the past 24 hours on a numeric rating scale anchored by the terms No itching (0) and Worst possible itching (10) at the ends. Baseline-C defined as the last observation up to first dosing date in Period C. | Weeks 4, 8, and 16 (Period C) | 
| Percentage of Participants With ISI Score of 0 During the Initial CP-690,550 Treatment (Period A) | The severity of itch (pruritus) due to psoriasis was assessed using the ISI, a single item, horizontal numeric rating scale. Participants were asked to rate your worst itching due to psoriasis over the past 24 hours on a numeric rating scale anchored by the terms No itching (0) and Worst possible itching (10) at the ends. | Weeks 4, 8, 16, and 24 (Period A) | 
| Percentage of Participants With ISI Score of 0 During CP-690,550 Re-Treatment (Period C) | The severity of itch (pruritus) due to psoriasis was assessed using the ISI, a single item, horizontal numeric rating scale. Participants were asked to rate your worst itching due to psoriasis over the past 24 hours on a numeric rating scale anchored by the terms No itching (0) and Worst possible itching (10) at the ends. | Baseline and Weeks 4, 8, and 16 (Period C) | 
| Percentage of Participants Achieving ISI Score of ≤1 During the Initial CP-690,550 Treatment (Period A) | The severity of itch (pruritus) due to psoriasis was assessed using the ISI, a single item, horizontal numeric rating scale. Participants were asked to rate your worst itching due to psoriasis over the past 24 hours on a numeric rating scale anchored by the terms No itching (0) and Worst possible itching (10) at the ends. | Weeks 4, 8, 16, and 24 (Period A) | 
| Percentage of Participants Achieving an ISI Score of ≤1 During CP-690,550 Re-Treatment (Period C) | The severity of itch (pruritus) due to psoriasis was assessed using the ISI, a single item, horizontal numeric rating scale. Participants were asked to rate your worst itching due to psoriasis over the past 24 hours on a numeric rating scale anchored by the terms No itching (0) and Worst possible itching (10) at the ends. | Baseline and Weeks 4, 8, and 16 (Period C) | 
| Percentage of Participants Achieving ISI ≥2-Point Reduction During the Initial CP-690,550 Treatment (Period A) | The severity of itch (pruritus) due to psoriasis was assessed using the ISI, a single item, horizontal numeric rating scale. Participants were asked to rate your worst itching due to psoriasis over the past 24 hours on a numeric rating scale anchored by the terms No itching (0) and Worst possible itching (10) at the ends. | Weeks 4, 8, 16, and 24 (Period A) | 
| Percentage of Participants Achieving ISI ≥2-Point Reduction During the CP-690,550 Re-Treatment (Period C) | The severity of itch (pruritus) due to psoriasis was assessed using the ISI, a single item, horizontal numeric rating scale. Participants were asked to rate your worst itching due to psoriasis over the past 24 hours on a numeric rating scale anchored by the terms No itching (0) and Worst possible itching (10) at the ends. | Weeks 4, 8, and 16 (Period C) | 
| ISI Score of ≤1 During the Initial CP-690,550 Treatment (Period A) - Percentage of Participants With a Response | The severity of itch (pruritus) due to psoriasis was assessed using the ISI, a single item, horizontal numeric rating scale. Participants were asked to rate your worst itching due to psoriasis over the past 24 hours on a numeric rating scale anchored by the terms No itching (0) and Worst possible itching (10) at the ends. | Weeks 4, 8, 16, and 24 (Period A) | 
| Median Time to ISI Score of ≤1 During the Initial CP-690,550 Treatment (Period A) | The severity of itch (pruritus) due to psoriasis was assessed using the ISI, a single item, horizontal numeric rating scale. Participants were asked to rate your worst itching due to psoriasis over the past 24 hours on a numeric rating scale anchored by the terms No itching (0) and Worst possible itching (10) at the ends. | Weeks 4, 8, 16, and 24 (Period A) | 
| ISI Score of ≤1 During CP-690,550 Re-Treatment (Period C) - Percentage of Participants With a Response | The severity of itch (pruritus) due to psoriasis was assessed using the ISI, a single item, horizontal numeric rating scale. Participants were asked to rate your worst itching due to psoriasis over the past 24 hours on a numeric rating scale anchored by the terms No itching (0) and Worst possible itching (10) at the ends. | Weeks 4, 8, and 16 (Period C) | 
| Median Time to ISI Score of ≤1 During the CP-690,550 Re-Treatment (Period C) | The severity of itch (pruritus) due to psoriasis was assessed using the ISI, a single item, horizontal numeric rating scale. Participants were asked to rate your worst itching due to psoriasis over the past 24 hours on a numeric rating scale anchored by the terms No itching (0) and Worst possible itching (10) at the ends. | Weeks 4, 8, and 16 (Period C) | 
| ISI Reduction (2-point Decrease in ISI Score) During the Initial CP-690,550 Treatment (Period A) - Percentage of Participants With a Response | The severity of itch (pruritus) due to psoriasis was assessed using the ISI, a single item, horizontal numeric rating scale. Participants were asked to rate your worst itching due to psoriasis over the past 24 hours on a numeric rating scale anchored by the terms No itching (0) and Worst possible itching (10) at the ends. | Weeks 4, 8, 16, and 24 (Period A) | 
| Median Time to ISI Reduction (2-point Decrease in ISI Score) During the Initial CP-690,550 Treatment (Period A) | The severity of itch (pruritus) due to psoriasis was assessed using the ISI, a single item, horizontal numeric rating scale. Participants were asked to rate your worst itching due to psoriasis over the past 24 hours on a numeric rating scale anchored by the terms No itching (0) and Worst possible itching (10) at the ends. | Weeks 4, 8, 16, and 24 (Period A) | 
| ISI Reduction (2-point Decrease in ISI Score) During the CP-690,550 Re-Treatment (Period C) - Percentage of Participant With a Response | The severity of itch (pruritus) due to psoriasis was assessed using the ISI, a single item, horizontal numeric rating scale. Participants were asked to rate your worst itching due to psoriasis over the past 24 hours on a numeric rating scale anchored by the terms No itching (0) and Worst possible itching (10) at the ends. | Weeks 4, 8, and 16 (Period C) | 
| Median Time to ISI Reduction (2-point Decrease in ISI Score) During the CP-690,550 Re-Treatment (Period C) | The severity of itch (pruritus) due to psoriasis was assessed using the ISI, a single item, horizontal numeric rating scale. Participants were asked to rate your worst itching due to psoriasis over the past 24 hours on a numeric rating scale anchored by the terms No itching (0) and Worst possible itching (10) at the ends. | Weeks 4, 8, and 16 (Period C) | 
| Mean Dermatology Life Quality Index (DLQI) Score During the Initial CP-690,550 Treatment (Period A) | The DLQI is a general dermatology questionnaire that consists of 10 items that assess health related quality of life (daily activities, personal relationships, symptoms and feelings, leisure, work and school, and treatment). The DLQI questions are rated by the participant as 0 (not at all/not relevant) to 3 (very much) with a total score range of 0 (best) to 30 (worst); higher scores indicate poor quality of life. | Baseline and Weeks 4, 8, 16, and 24 (Period A) | 
| Mean DLQI Score During the CP-690,550 Re-Treatment (Period C) | The DLQI is a general dermatology questionnaire that consists of 10 items that assess health related quality of life (daily activities, personal relationships, symptoms and feelings, leisure, work and school, and treatment). The DLQI questions are rated by the participant as 0 (not at all/not relevant) to 3 (very much) with a total score range of 0 (best) to 30 (worst); higher scores indicate poor quality of life. | Baseline and Weeks 4, 8, and 16 (Period C) | 
| Mean DLQI Score During the Double-Blind Treatment Withdrawal (Period B) | The DLQI is a general dermatology questionnaire that consists of 10 items that assess health related quality of life (daily activities, personal relationships, symptoms and feelings, leisure, work and school, and treatment). The DLQI questions are rated by the participant as 0 (not at all/not relevant) to 3 (very much) with a total score range of 0 (best) to 30 (worst); higher scores indicate poor quality of life. | Baseline and Weeks 4, 8, 12, and 16 (Period B) | 
| Mean Change From Baseline-A in DLQI Score During the Initial CP-690,550 Treatment (Period A) | The DLQI is a general dermatology questionnaire that consists of 10 items that assess health related quality of life (daily activities, personal relationships, symptoms and feelings, leisure, work and school, and treatment). The DLQI questions are rated by the participant as 0 (not at all/not relevant) to 3 (very much) with a total score range of 0 (best) to 30 (worst); higher scores indicate poor quality of life. The minimally important difference for the DLQI has been estimated as a 2 to 5 point change from baseline. Baseline-A defined as the last observation up to first dosing date in Period A. | Weeks 4, 8, 16, and 24 (Period A) | 
| Mean Change From Baseline-B in DLQI Score During the Double-Blind Treatment Withdrawal (Period B) | The DLQI is a general dermatology questionnaire that consists of 10 items that assess health related quality of life (daily activities, personal relationships, symptoms and feelings, leisure, work and school, and treatment). The DLQI questions are rated by the participant as 0 (not at all/not relevant) to 3 (very much) with a total score range of 0 (best) to 30 (worst); higher scores indicate poor quality of life. The minimally important difference for the DLQI has been estimated as a 2 to 5 point change from baseline. Baseline-B defined as the last observation up to first dosing date in Period B. | Weeks 4, 8, 12, and 16 (Period B) | 
| Mean Change From Baseline-C in DLQI Score During the CP-690,550 Re-Treatment (Period C) | The DLQI is a general dermatology questionnaire that consists of 10 items that assess health related quality of life (daily activities, personal relationships, symptoms and feelings, leisure, work and school, and treatment). The DLQI questions are rated by the participant as 0 (not at all/not relevant) to 3 (very much) with a total score range of 0 (best) to 30 (worst); higher scores indicate poor quality of life. The minimally important difference for the DLQI has been estimated as a 2 to 5 point change from baseline. Baseline-C defined as the last observation up to first dosing date in Period C. | Weeks 4, 8, and 16 (Period C) | 
| Mean DLQI Subscale Scores During the Initial CP-690,550 Treatment (Period A) | The DLQI is a general dermatology questionnaire that consists of 10 items that assess health related quality of life (daily activities, personal relationships, symptoms and feelings, leisure, work and school, and treatment). The DLQI questions are rated by the participant as 0 (not at all/not relevant) to 3 (very much); higher scores indicate poor quality of life. The DLQI can be analyzed under 6 subscales by combining questions and is categorized as follows: symptoms and feelings (maximum score=6); daily activities (maximum score=6); leisure (maximum score=6); work and school (maximum score=3); personal relationships (maximum score=6); and treatment (maximum score=3). | Baseline and Weeks 4, 8, 16, and 24 (Period A) | 
| Mean DLQI Subscale Scores During the Double-Blind Treatment Withdrawal (Period B) | The DLQI is a general dermatology questionnaire that consists of 10 items that assess health related quality of life (daily activities, personal relationships, symptoms and feelings, leisure, work and school, and treatment). The DLQI questions are rated by the participant as 0 (not at all/not relevant) to 3 (very much); higher scores indicate poor quality of life. The DLQI can be analyzed under 6 subscales by combining questions and is categorized as follows: symptoms and feelings (maximum score=6); daily activities (maximum score=6); leisure (maximum score=6); work and school (maximum score=3); personal relationships (maximum score=6); and treatment (maximum score=3). | Baseline and Weeks 4, 8, 12, and 16 (Period B) | 
| Mean DLQI Subscale Scores During the CP-690,550 Re-Treatment (Period C) | The DLQI is a general dermatology questionnaire that consists of 10 items that assess health related quality of life (daily activities, personal relationships, symptoms and feelings, leisure, work and school, and treatment). The DLQI questions are rated by the participant as 0 (not at all/not relevant) to 3 (very much); higher scores indicate poor quality of life. The DLQI can be analyzed under 6 subscales by combining questions and is categorized as follows: symptoms and feelings (maximum score=6); daily activities (maximum score=6); leisure (maximum score=6); work and school (maximum score=3); personal relationships (maximum score=6); and treatment (maximum score=3). | Baseline and Weeks 4, 8, and 16 (Period C) | 
| Mean Change From Baseline-A in DLQI Subscale Scores During the Initial CP-690,550 Treatment (Period A) | The DLQI is a general dermatology questionnaire that consists of 10 items that assess health related quality of life (daily activities, personal relationships, symptoms and feelings, leisure, work and school, and treatment). The DLQI questions are rated by the participant as 0 (not at all/not relevant) to 3 (very much); higher scores indicate poor quality of life. The DLQI can be analyzed under 6 subscales by combining questions and is categorized as follows: symptoms and feelings (maximum score=6); daily activities (maximum score=6); leisure (maximum score=6); work and school (maximum score=3); personal relationships (maximum score=6); and treatment (maximum score=3). The minimally important difference for the DLQI has been estimated as a 2 to 5 point change from baseline. Baseline-A defined as the last observation up to first dosing date in Period A. | Weeks 4, 8, 16, and 24 (Period A) | 
| Mean Change From Baseline-B in DLQI Subscale Scores During the Double-Blind Treatment Withdrawal (Period B) | The DLQI is a general dermatology questionnaire that consists of 10 items that assess health related quality of life (daily activities, personal relationships, symptoms and feelings, leisure, work and school, and treatment). The DLQI questions are rated by the participant as 0 (not at all/not relevant) to 3 (very much); higher scores indicate poor quality of life. The DLQI can be analyzed under 6 subscales by combining questions and is categorized as follows: symptoms and feelings (maximum score=6); daily activities (maximum score=6); leisure (maximum score=6); work and school (maximum score=3); personal relationships (maximum score=6); and treatment (maximum score=3). The minimally important difference for the DLQI has been estimated as a 2 to 5 point change from baseline. Baseline-B defined as the last observation up to first dosing date in Period B. | Weeks 4, 8, 12, and 16 (Period B) | 
| Mean Change From Baseline-C in DLQI Subscale Scores During the CP-690,550 Re-Treatment (Period C) | The DLQI is a general dermatology questionnaire that consists of 10 items that assess health related quality of life (daily activities, personal relationships, symptoms and feelings, leisure, work and school, and treatment). The DLQI questions are rated by the participant as 0 (not at all/not relevant) to 3 (very much); higher scores indicate poor quality of life. The DLQI can be analyzed under 6 subscales by combining questions and is categorized as follows: symptoms and feelings (maximum score=6); daily activities (maximum score=6); leisure (maximum score=6); work and school (maximum score=3); personal relationships (maximum score=6); and treatment (maximum score=3). The minimally important difference for the DLQI has been estimated as a 2 to 5 point change from baseline. Baseline-C defined as the last observation up to first dosing date in Period C. | Weeks 4, 8, and 16 (Period C) | 
| Percentage of Participants Achieving DLQI ≥5 Point Reduction From Baseline-A Response During Initial CP-690,550 Treatment (Period A) | The DLQI is a general dermatology questionnaire that consists of 10 items that assess health related quality of life (daily activities, personal relationships, symptoms and feelings, leisure, work and school, and treatment). The DLQI questions are rated by the participant as 0 (not at all/not relevant) to 3 (very much) with a total score range of 0 (best) to 30 (worst); higher scores indicate poor quality of life. The minimally important difference for the DLQI has been estimated as a 2 to 5 point change from baseline. | Weeks 4, 8, 16, and 24 (Period A) | 
| Percentage of Participants Achieving DLQI ≥5 Point Reduction From Baseline-B Response During Double-Blind Treatment Withdrawal (Period B) | The DLQI is a general dermatology questionnaire that consists of 10 items that assess health related quality of life (daily activities, personal relationships, symptoms and feelings, leisure, work and school, and treatment). The DLQI questions are rated by the participant as 0 (not at all/not relevant) to 3 (very much) with a total score range of 0 (best) to 30 (worst); higher scores indicate poor quality of life. The minimally important difference for the DLQI has been estimated as a 2 to 5 point change from baseline. | Weeks 4, 8, 12, and 16 (Period B) | 
| Percentage of Participants Achieving DLQI ≥5 Point Reduction From Baseline-C Response During CP-690,550 Re-Treatment (Period C) | The DLQI is a general dermatology questionnaire that consists of 10 items that assess health related quality of life (daily activities, personal relationships, symptoms and feelings, leisure, work and school, and treatment). The DLQI questions are rated by the participant as 0 (not at all/not relevant) to 3 (very much) with a total score range of 0 (best) to 30 (worst); higher scores indicate poor quality of life. The minimally important difference for the DLQI has been estimated as a 2 to 5 point change from baseline. Baseline-C defined as the last observation up to first dosing date in Period C. | Weeks 4, 8, and 16 (Period C) | 
| Percentage of Participants Achieving DLQI ≤1 Response During the Initial CP-690,550 Treatment (Period A) | The DLQI is a general dermatology questionnaire that consists of 10 items that assess health related quality of life (daily activities, personal relationships, symptoms and feelings, leisure, work and school, and treatment). The DLQI questions are rated by the participant as 0 (not at all/not relevant) to 3 (very much) with a total score range of 0 (best) to 30 (worst); higher scores indicate poor quality of life. The minimally important difference for the DLQI has been estimated as a 2 to 5 point change from baseline. | Weeks 4, 8, 16, and 24 (Period A) | 
| Percentage of Participants Achieving DLQI ≤1 Response During Double-Blind Treatment Withdrawal (Period B) | The DLQI is a general dermatology questionnaire that consists of 10 items that assess health related quality of life (daily activities, personal relationships, symptoms and feelings, leisure, work and school, and treatment). The DLQI questions are rated by the participant as 0 (not at all/not relevant) to 3 (very much) with a total score range of 0 (best) to 30 (worst); higher scores indicate poor quality of life. The minimally important difference for the DLQI has been estimated as a 2 to 5 point change from baseline. | Weeks 4, 8, 12, and 16 (Period B) | 
| Percentage of Participants Achieving DLQI ≤1 Response During CP-690,550 Re-Treatment (Period C) | The DLQI is a general dermatology questionnaire that consists of 10 items that assess health related quality of life (daily activities, personal relationships, symptoms and feelings, leisure, work and school, and treatment). The DLQI questions are rated by the participant as 0 (not at all/not relevant) to 3 (very much) with a total score range of 0 (best) to 30 (worst); higher scores indicate poor quality of life. The minimally important difference for the DLQI has been estimated as a 2 to 5 point change from baseline. | Baseline and Weeks 4, 8, and 16 (Period C) | 
| Percentage of Participants by DLQI Severity Category During the Initial CP-690,550 Treatment (Period A) | The DLQI is a general dermatology questionnaire that consists of 10 items that assess health related quality of life (daily activities, personal relationships, symptoms and feelings, leisure, work and school, and treatment). Severity is measured using the following categories of scores: 0-1=no effect on patients' lives; 2-5=small effect; 6-10=moderate effect; 11-20=very large effect; 21-30=extremely large effect. | Baseline and Weeks 4, 8, 16, and 24 (Period A) | 
| Percentage of Participants With DLQI ≥5-Point Reduction From Baseline-A Response During Initial CP-690,550 Treatment (Period A) | The DLQI is a general dermatology questionnaire that consists of 10 items that assess health related quality of life (daily activities, personal relationships, symptoms and feelings, leisure, work and school, and treatment). The DLQI questions are rated by the participant as 0 (not at all/not relevant) to 3 (very much) with a total score range of 0 (best) to 30 (worst); higher scores indicate poor quality of life. The minimally important difference for the DLQI has been estimated as a 2 to 5 point change from baseline. | Weeks 4, 8, 16, and 24 (Period A) | 
| Median Time to DLQI ≥5-Point Reduction From Baseline-A Response During Initial CP-690,550 Treatment (Period A) | The DLQI is a general dermatology questionnaire that consists of 10 items that assess health related quality of life (daily activities, personal relationships, symptoms and feelings, leisure, work and school, and treatment). The minimally important difference for the DLQI has been estimated as a 2 to 5 point change from baseline. | Weeks 4, 8, 16, and 24 (Period A) | 
| Percentage of Participants With DLQI ≥5-Point Reduction From Baseline-A Response During CP-690,550 Re-Treatment (Period C) | The DLQI is a general dermatology questionnaire that consists of 10 items that assess health related quality of life (daily activities, personal relationships, symptoms and feelings, leisure, work and school, and treatment). The DLQI questions are rated by the participant as 0 (not at all/not relevant) to 3 (very much) with a total score range of 0 (best) to 30 (worst); higher scores indicate poor quality of life. The minimally important difference for the DLQI has been estimated as a 2 to 5 point change from baseline. | Weeks 4, 8, and 16 (Period C) | 
| Median Time to DLQI ≥5-Point Reduction From Baseline-A Response During CP-690,550 Re-Treatment (Period C) | The DLQI is a general dermatology questionnaire that consists of 10 items that assess health related quality of life (daily activities, personal relationships, symptoms and feelings, leisure, work and school, and treatment). The minimally important difference for the DLQI has been estimated as a 2 to 5 point change from baseline. | Weeks 4, 8, and 16 (Period C) | 
| Mean Short-Form 36 (SF-36) Physical Component Summary (PCS) and Mental Component Summary (MCS) Scores During the Initial CP-690,550 Treatment (Period A) | The SF-36 is a general health status questionnaire that assesses 8 domains of functional health and well being: Physical Functioning, Role Limitations due to Physical Health Problems, Bodily Pain, Social Functioning, Mental Health, Role Limitations due to Emotional Problems, Vitality, and General Health Perceptions. The score for a section is an average of the individual question scores, which are scaled 0-100 (100=highest level of functioning). A PCS score and MCS score are based on a normalized sum of the 8 scale scores; PCS/MCS summary concept score = (raw score*10) plus 50. Linear transformations were performed to transform scores to a mean of 50 and standard deviations (SDs) of 10, in the general population. In norm-based scoring, each scale is scored to have same average (50)/SD (10). With this method anytime a scale score is below 50, health status is below average, and each point is one-tenth of a SD. Higher scores indicate a better health related quality of life. | Baseline and Week 24 (Period A) | 
| Mean SF-36 PCS and MCS Scores During CP-690,550 Re-Treatment (Period C) | The SF-36 is a general health status questionnaire that assesses 8 domains of functional health and well being: Physical Functioning, Role Limitations due to Physical Health Problems, Bodily Pain, Social Functioning, Mental Health, Role Limitations due to Emotional Problems, Vitality, and General Health Perceptions. The score for a section is an average of the individual question scores, which are scaled 0-100 (100=highest level of functioning). A PCS score and MCS score are based on a normalized sum of the 8 scale scores; PCS/MCS summary concept score = (raw score*10) plus 50. Linear transformations were performed to transform scores to a mean of 50 and SDs of 10, in the general population. In norm-based scoring, each scale is scored to have same average (50)/SD (10). With this method anytime a scale score is below 50, health status is below average, and each point is one-tenth of a SD. Higher scores indicate a better health related quality of life. | Baseline and Week 56 (Period C) | 
| Mean Change From Baseline-A in SF-36 PCS and MCS Scores During the Initial CP-690,550 Treatment (Period A) | The SF-36 is a general health status questionnaire that assesses 8 domains of functional health and well being: Physical Functioning, Role Limitations due to Physical Health Problems, Bodily Pain, Social Functioning, Mental Health, Role Limitations due to Emotional Problems, Vitality, and General Health Perceptions. The score for a section is an average of the individual question scores, which are scaled 0-100 (100=highest level of functioning). A PCS score and MCS score are based on a normalized sum of the 8 scale scores; PCS/MCS summary concept score = (raw score*10) plus 50. Linear transformations were performed to transform scores to a mean of 50 and SDs of 10, in the general population. In norm-based scoring, each scale is scored to have same average (50)/SD (10). With this method anytime a scale score is below 50, health status is below average, and each point is one-tenth of a SD. Higher scores indicate a better health related quality of life. | Week 24 (Period A) | 
| Mean Change From Baseline-C in SF-36 PCS and MCS Scores During CP-690,550 Re-Treatment (Period C) | The SF-36 is a general health status questionnaire that assesses 8 domains of functional health and well being: Physical Functioning, Role Limitations due to Physical Health Problems, Bodily Pain, Social Functioning, Mental Health, Role Limitations due to Emotional Problems, Vitality, and General Health Perceptions. The score for a section is an average of the individual question scores, which are scaled 0-100 (100=highest level of functioning). A PCS score and MCS score are based on a normalized sum of the 8 scale scores; PCS/MCS summary concept score = (raw score*10) plus 50. Linear transformations were performed to transform scores to a mean of 50 and SDs of 10, in the general population. In norm-based scoring, each scale is scored to have same average (50)/SD (10). With this method anytime a scale score is below 50, health status is below average, and each point is one-tenth of a SD. Higher scores indicate a better health related quality of life. | Week 56 (Period C) | 
| Mean SF-36 Domain Scores During the Initial CP-690,550 Treatment (Period A) | The SF-36 is a general health status questionnaire that assesses 8 domains of functional health and well being: Physical Functioning, Role Limitations due to Physical Health Problems, Bodily Pain, Social Functioning, Mental Health, Role Limitations due to Emotional Problems, Vitality, and General Health Perceptions. The score for a section is an average of the individual question scores, which are scaled 0-100 (100=highest level of functioning). Higher scores indicate a better health related quality of life. | Baseline and Week 24 (Period A) | 
| Mean SF-36 Domain Scores During CP-690,550 Re-Treatment (Period C) | The SF-36 is a general health status questionnaire that assesses 8 domains of functional health and well being: Physical Functioning, Role Limitations due to Physical Health Problems, Bodily Pain, Social Functioning, Mental Health, Role Limitations due to Emotional Problems, Vitality, and General Health Perceptions. The score for a section is an average of the individual question scores, which are scaled 0-100 (100=highest level of functioning). Higher scores indicate a better health related quality of life. | Baseline and Week 56 (Period C) | 
| Mean Change From Baseline-A in SF-36 Domain Scores During the Initial CP-690,550 Treatment (Period A) | The SF-36 is a general health status questionnaire that assesses 8 domains of functional health and well being: Physical Functioning, Role Limitations due to Physical Health Problems, Bodily Pain, Social Functioning, Mental Health, Role Limitations due to Emotional Problems, Vitality, and General Health Perceptions. The score for a section is an average of the individual question scores, which are scaled 0-100 (100=highest level of functioning). Higher scores indicate a better health related quality of life. Baseline-A defined as the last observation up to first dosing date in Period A. | Week 24 (Period A) | 
| Mean Change From Baseline-C in SF-36 Domain Scores During CP-690,550 Re-Treatment (Period C) | The SF-36 is a general health status questionnaire that assesses 8 domains of functional health and well being: Physical Functioning, Role Limitations due to Physical Health Problems, Bodily Pain, Social Functioning, Mental Health, Role Limitations due to Emotional Problems, Vitality, and General Health Perceptions. The score for a section is an average of the individual question scores, which are scaled 0-100 (100=highest level of functioning). Higher scores indicate a better health related quality of life. Baseline-C defined as the last observation up to first dosing date in Period C. | Week 56 (Period C) | 
| Percentage of Participants in Each Patient Global Assessment (PtGA) of Psoriasis Category During the Initial CP-690,550 Treatment (Period A) | The PtGA asks the participant to evaluate the overall cutaneous disease at that point in time on a single item, 5 point scale. The scale is scored as follows: 0=clear; 1=almost clear; 2=mild; 3=moderate; and 4=severe | Baseline and Weeks 4, 8, 16 and 24 (Period A) | 
| Percentage of Participants in Each PtGA of Psoriasis Category During Double-Blind Treatment Withdrawal (Period B) | The PtGA asks the participant to evaluate the overall cutaneous disease at that point in time on a single item, 5 point scale. The scale is scored as follows: 0=clear; 1=almost clear; 2=mild; 3=moderate; and 4=severe. | Baseline and Weeks 4, 8, 12, and 16 (Period B) | 
| Percentage of Participants in Each PtGA of Psoriasis Category During CP-690,550 Re-Treatment (Period C) | The PtGA asks the participant to evaluate the overall cutaneous disease at that point in time on a single item, 5 point scale. The scale is scored as follows: 0=clear; 1=almost clear; 2=mild; 3=moderate; and 4=severe. | Baseline and Weeks 4, 8, and 16 (Period C) | 
| Percentage of Participants With PtGA Response of Clear or Almost Clear During the Initial CP-690,550 Treatment (Period A) | The PtGA asks the participant to evaluate the overall cutaneous disease at that point in time on a single item, 5 point scale. The scale is scored as follows: 0=clear; 1=almost clear; 2=mild; 3=moderate; and 4=severe. Response defined as score of 0 or 1. | Weeks 4, 8, 16, and 24 (Period A) | 
| Percentage of Participants With PtGA Response of Clear or Almost Clear During CP-690,550 Re-Treatment (Period C) Among Participants Who Had a PtGA of Mild, Moderate or Severe During CP-690,550 Treatment Withdrawal (Period B) | The PtGA asks the participant to evaluate the overall cutaneous disease at that point in time on a single item, 5 point scale. The scale is scored as follows: 0=clear; 1=almost clear; 2=mild; 3=moderate; and 4=severe. Response defined as score of 0 or 1. | Baseline and Weeks 4, 8, and 16 (Period C) | 
| Percentage of Participants Maintaining PtGA Response of Clear or Almost Clear During the Double-Blind Treatment Withdrawal (Period B) Among Participants Who Had a Response of Clear or Almost Clear at Beginning of Period B | The PtGA asks the participant to evaluate the overall cutaneous disease at that point in time on a single item, 5 point scale. The scale is scored as follows: 0=clear; 1=almost clear; 2=mild; 3=moderate; and 4=severe. Response defined as score of 0 or 1. | Weeks 4, 8, 12, and 16 (Period B) | 
| Mean EuroQol 5 Dimensions (EQ-5D) Health State Profile Utility Score and VAS Scores During the Initial CP-690,550 Treatment Period (Period A) | EQ-5D: participant rated questionnaire to assess health-related quality of life in terms of a single utility score. Health State Profile component assesses level of current health for 5 domains: mobility, self-care, usual activities, pain and discomfort, and anxiety and depression; 1 indicates better health state (no problems); 3 indicates worst health state (confined to bed). Scoring formula developed by EuroQol Group assigns a utility value for each domain in the profile. Score is transformed and results in a total score range -0.594 to 1.000; higher score indicates a better health state. The VAS component rates current health state on a scale from 0 (worst imaginable health state) to 100 (best imaginable health state); higher scores indicate a better health state. | Weeks 4, 8, 16, and 24 (Period A) | 
| Mean EQ-5D Utility Score and VAS Scores During CP-690,550 Re-Treatment (Period C) | EQ-5D: participant rated questionnaire to assess health-related quality of life in terms of a single utility score. Health State Profile component assesses level of current health for 5 domains: mobility, self-care, usual activities, pain and discomfort, and anxiety and depression; 1 indicates better health state (no problems); 3 indicates worst health state (confined to bed). Scoring formula developed by EuroQol Group assigns a utility value for each domain in the profile. Score is transformed and results in a total score range -0.594 to 1.000; higher score indicates a better health state. The VAS component rates current health state on a scale from 0 (worst imaginable health state) to 100 (best imaginable health state); higher scores indicate a better health state. | Baseline and Week 56 (Period C) | 
| Mean Change From Baseline-A in EQ-5D Utility Score and VAS Scores During the Initial CP-690,550 Treatment Period (Period A) | EQ-5D: participant rated questionnaire to assess health-related quality of life in terms of a single utility score. Health State Profile component assesses level of current health for 5 domains: mobility, self-care, usual activities, pain and discomfort, and anxiety and depression; 1 indicates better health state (no problems); 3 indicates worst health state (confined to bed). Scoring formula developed by EuroQol Group assigns a utility value for each domain in the profile. Score is transformed and results in a total score range -0.594 to 1.000; higher score indicates a better health state. The VAS component rates current health state on a scale from 0 (worst imaginable health state) to 100 (best imaginable health state); higher scores indicate a better health state. Baseline-A defined as the last observation up to first dosing date in Period A. | Week 24 (Period A) | 
| Mean Change From Baseline-C in EQ-5D Utility Score and VAS Scores During CP-690,550 Re-Treatment (Period C) | EQ-5D: participant rated questionnaire to assess health-related quality of life in terms of a single utility score. Health State Profile component assesses level of current health for 5 domains: mobility, self-care, usual activities, pain and discomfort, and anxiety and depression; 1 indicates better health state (no problems); 3 indicates worst health state (confined to bed). Scoring formula developed by EuroQol Group assigns a utility value for each domain in the profile. Score is transformed and results in a total score range -0.594 to 1.000; higher score indicates a better health state. The VAS component rates current health state on a scale from 0 (worst imaginable health state) to 100 (best imaginable health state); higher scores indicate a better health state. Baseline-C defined as the last observation up to first dosing date in Period C. | Week 56 (Period C) | 
| Mean EQ-5D Domain Scores During the Initial CP-690,550 Treatment Period (Period A) | EQ-5D: participant rated questionnaire to assess health-related quality of life in terms of a single utility score. Health State Profile component assesses level of current health for 5 domains: mobility, self-care, usual activities, pain and discomfort, and anxiety and depression. The score for each of the 5 dimensions can range from 1 to 3; 1 indicates better health state (no problems); 3 indicates worst health state (confined to bed). | Baseline and Week 24 (Period A) | 
| Mean EQ-5D Domain Scores During CP-690,550 Re-Treatment (Period C) | EQ-5D: participant rated questionnaire to assess health-related quality of life in terms of a single utility score. Health State Profile component assesses level of current health for 5 domains: mobility, self-care, usual activities, pain and discomfort, and anxiety and depression. The score for each of the 5 dimensions can range from 1 to 3; 1 indicates better health state (no problems); 3 indicates worst health state (confined to bed). | Baseline and Week 56 (Period C) | 
| Mean Change From Baseline-A in EQ-5D Domain Scores During the Initial CP-690,550 Treatment Period (Period A) | EQ-5D: participant rated questionnaire to assess health-related quality of life in terms of a single utility score. Health State Profile component assesses level of current health for 5 domains: mobility, self-care, usual activities, pain and discomfort, and anxiety and depression. The score for each of the 5 dimensions can range from 1 to 3; 1 indicates better health state (no problems); 3 indicates worst health state (confined to bed). Baseline-A defined as the last observation up to first dosing date in Period A. | Week 24 (Period A) | 
| Mean Change From Baseline-C in EQ-5D Domain Scores During CP-690,550 Re-Treatment (Period C) | EQ-5D: participant rated questionnaire to assess health-related quality of life in terms of a single utility score. Health State Profile component assesses level of current health for 5 domains: mobility, self-care, usual activities, pain and discomfort, and anxiety and depression. The score for each of the 5 dimensions can range from 1 to 3; 1 indicates better health state (no problems); 3 indicates worst health state (confined to bed). Baseline-C defined as the last observation up to first dosing date in Period C. | Week 56 (Period C) | 
| Percentage of Participants With Pustular, Erythrodermic, or Guttate Psoriasis During the Initial CP-690,550 Treatment (Period A) |  | Weeks 4, 8, 16, and 24 (Period A) | 
| Percentage of Participants With Pustular, Erythrodermic, or Guttate Psoriasis During Double-Blind Treatment Withdrawal (Period B) |  | Weeks 4, 8, 12, and 16 (Period B) | 
| Percentage of Participants With Pustular, Erythrodermic, or Guttate Psoriasis During CP-690,550 Re-Treatment (Period C) |  | Weeks 4, 8, and 16 (Period C) | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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OPT Retreatment, OPT, chronic, moderate, severe, treatment, safety, treatment withdrawal, retreatment, retreatment withdrawal, CP-690,550, Psoriasis Vulgaris, Plaque Psoriasis, tofacitinib, Xeljanz, nail psoriasis, Jak-inhibitor, oral treatment, Pruritus, Itch, DLQI, rebound, intermittent, retreat