Immunologic Response to Secukinumab in Plaque Psoriasis

Inclusion Criteria: 1. Ability to provide written informed consent and comply with the protocol. 2. At least 18 years of age. 3. Diagnosis of predominately plaque psoriasis for at least 6 months prior to enrollment. 4. Subject is considered a candidate for phototherapy or systemic therapy 5. PASI ≥ 12 6. PGA ≥ 3 7. Subject has a negative Quantiferon Gold, or if positive undergoes CXR. If CXR negative, subject initiated prophylactic therapy with isoniazid for a course of 9 months with one month of therapy completed prior to first dose of secukinumab. 8. Subject is unlikely to conceive (male, post-menopausal, or using adequate oral contraceptive therapy or IUD). 9. Physical exam within clinically acceptable limits. Exclusion Criteria: 1. Subject is unable to provide written informed consent or comply with the protocol. 2. Subject is younger than 18 years of age. 3. Subject has predominately non-plaque form of psoriasis. 4. Subject with mild psoriasis (PASI\<12 and PGA\<3) or is not a candidate for phototherapy or systemic treatments. 5. Subject has drug-induced psoriasis. 6. Subject with current, or a history of, severe psoriatic arthritis well controlled on current therapy. 7. Subjects with a serum creatinine level exceeding 176.8 μmol/L (2.0 mg/dl). 8. Screening total white blood cell (WBC count) \< 2,500/μl, platelets \< 100,000/μl, neutrophils \< 1,500/μl, or hemoglobin \<8.5 g/dl. 9. Evidence of active tuberculosis infection as defined by a positive QuantiFERON TB-Gold test (QFT) with a positive chest X-ray at screening, or untreated latent tuberculosis defined by positive QFT with a negative chest X-ray without prophylactic therapy with isoniazid for a course of 9 months with one month of therapy completed prior to first dose of secukinumab. 10. History of an ongoing, chronic or recurrent infectious disease including past medical history record of HIV, hepatitis B or hepatitis C. 11. Subjects possess other diagnoses that, in the investigator's opinion, preclude him/her from safely participating in this study or interfere with the evaluation of the subject's psoriasis. 12. History of known or suspected intolerance to any of the ingredients of the investigational study product.