Inclusion Criteria:
1. Subject is ≥ 4 years and \< 18 years of age;
2. Subject weighs ≥ 13 kg;
3. Subject must have failed to respond to topical therapy;
4. Subject must need systemic treatment to control his/her disease and meet one of the following:
* Physician's Global Assessment (PGA) ≥ 4
* Body surface area (BSA) involved \> 20%
* Very thick lesions with BSA \> 10%
* Psoriasis Area and Severity Index (PASI) \> 20
* PASI \> 10 and at least one of the following:
* Active psoriatic arthritis unresponsive to non-steroid anti-inflammatory drugs (NSAIDs)
* Clinically relevant facial involvement
* Clinically relevant genital involvement
* Clinically relevant hand and/or foot involvement
* Children's Dermatology Life Quality Index (CDLQI) \> 10
5. If subject is \< 12 years of age and resides in a geographic region where heliotherapy is practical, subject must have failed to respond, be intolerant, or have a contraindication to heliotherapy, or is not a suitable candidate for heliotherapy;
6. If ≥ 12 years of age, subject must have failed to respond, be intolerant, or have a contraindication to phototherapy, or is not a suitable candidate for phototherapy;
7. Subject must have a clinical diagnosis of psoriasis for at least 6 months as determined by the subject's medical history and confirmation of diagnosis through physical examination by the Investigator;
8. Subject must have stable plaque psoriasis for at least 2 months prior to Baseline
Exclusion Criteria:
1. Prior biologic use other than prior treatment with etanercept;
2. Treatment with etanercept therapy within 4 weeks prior to the Baseline visit; 3. Methotrexate (MTX) use within the past year or prior MTX use at any time where the subject did not respond, or did not tolerate MTX;
4\. Contraindication for treatment with MTX during the study; 5. Erythrodermic psoriasis, generalized or localized pustular psoriasis, medication-induced or medication exacerbated psoriasis or new onset guttate psoriasis; 6. Infection(s) requiring treatment with intravenous (IV) anti-infectives within 30 days prior to the Baseline Visit or oral anti-infectives within 14 days prior to the Baseline Visit; 7. Treatment of psoriasis with topical therapies such as corticosteroids, vitamin D analogs, or retinoids within 7 days prior to the Baseline visit; 8. Treatment of psoriasis with ultraviolet (UV)B phototherapy, excessive sun exposure, or the use of tanning beds within 7 days prior to the Baseline visit; 9. Treatment of psoriasis with ultraviolet A with psoralen (PUVA) phototherapy, non-biologic systemic therapies for the treatment of psoriasis, or systemic therapies known to improve psoriasis within 14 days prior to the Baseline visit.
