Protocol for H.P. Acthar Gel in Moderately to Severely Active Psoriatic Arthritis

Inclusion Criteria: 1. In the opinion of the investigator, must have adequate reading and writing abilities (in their native language) such that the subject can comprehend and complete the informed consent, and all protocol-related assessments. 2. Age 18-75 years at the time of screening 3. Written informed consent and any locally required authorization (e.g. HIPAA) obtained from the subject prior to performing any protocol-related procedures, including screening evaluations. 4. Subject has had a diagnosis of psoriatic arthritis (by the Classification of Psoriatic Arthritis (CASPAR) criteria) for at least 6 months. 5. Subject must have \> 6 tender and \>6 swollen joint count at screening. 6. Subject must have \> 30 minutes of morning joint stiffness. 7. For subjects receiving non-steroidal anti-inflammatory drugs (NSAIDs) (including PRN use): the subject must be on stable dose for \>4 weeks prior to initiation of H.P. Acthar Gel. 8. For subjects receiving any Disease-Modifying Anti-Rheumatic Drug (DMARD) or Biologic agent: subject has received treatment for \>8 weeks, with a stable does for \> 4 weeks prior to initiation of H.P. Acthar Gel. 9. For subjects receiving oral corticosteroids: the subject must be on a stable dose (not to exceed the equivalent of 10mg of prednisone per day) for \>2 weeks prior to initiation of H.P. Acthar Gel. 10. Subject has a negative test for tuberculosis within 6 months before initiating H.P. Acthar Gel defined as either: * Negative purified protein derivative (PPD) * Negative Quantiferon test, or * Negative chest x-ray 11. Females of childbearing potential must use an effective method of birth control and avoid pregnancy from screening through 60 days after final dose of H.P. Acthar Gel unless surgically sterile (i.e. bilateral tubal ligation, bilateral oophorectomy, or complete hysterectomy), has a sterile male partner, is \>1 year postmenopausal or practices abstinence (not have sexual intercourse): \- Exclusion Criteria: 1. Subject has a planned surgical intervention between baseline and the week 24 evaluation. 2. Subject has any concurrent medical condition or uncontrolled, clinically significant systemic disease (eg, renal failure, congestive heart failure, uncontrolled hypertension, primary adrenocortical insufficiency or adrenocortical hyperfunction, peptic ulcer or sensitivity to proteins of porcine origin) 3. Subject has a diagnosis of scleroderma, osteoporosis, fungal infections or ocular herpes simplex 4. History of any type of malignancy \<5 years before enrollment into the study (apart from basal cell carcinoma) 5. Any live or attenuated vaccine within 4 weeks prior to signing the informed consent form (administration of killed vaccines is acceptable) 6. Subject has active tuberculosis 7. Any know history of allergy or reaction to any component of H.P. Acthar Gel 8. Known history of a primary immunodeficiency or an underlying condition such as human immunodeficiency virus (HIV) infection. 9. Employees of the clinical study site or any other individuals involved with the conduct of the study or immediate family members of such individuals 10. Concurrent enrollment in any other clinical study with an investigational product within 4 weeks prior to enrollment into the study. 11. Lactating or pregnant females or females who intend to become pregnant anytime from initiation of screening through 60 days post last dose of H.P. Acthar Gel \-