Patient description: A 53-year-old man presents with chronic HCV infection for the past 2 years. His past medical history is only significant for inguinal hernia surgery when he was 20 years old. He is on IFN (100 mg/week) plus RBV (400 mg/day) combination therapy for the past 9 months. Direct antiviral drugs were added to his treatment 6 months ago. His medical record shows previous positive HCV RNA tests as well as positive enzyme immunoassay for anti-HCV-antibodies. The recent biopsy was negative for hepatocellular carcinoma and was only remarkable for chronic inflammation compatible with a chronic viral hepatitis. There is no evidence of alcoholic liver disease, bleeding from esophageal varices, hemochromatosis, autoimmune hepatitis or metabolic liver disease. He is an alert male with no acute distress. His BP: 130/75, HR: 90/min and BMI: 27. His abdomen is soft with no ascites or tenderness. The lower extremities are normal with no edema.

Clinical trial eligibility criteria: eligible ages (years): 18.0-999.0,  Psoriatic Arthritis Patients eligible for in this study have to fulfil all of the following 1. Patient must be able to understand and communicate with the investigator and comply with the requirements of the study and must give a written, signed and dated informed consent before any study assessment is performed. 2. Male or non-pregnant, non-nursing female patients at least 18 years of age. Before randomization, a woman of childbearing potential must be on a highly effective method of birth control consistent with local regulations regarding the use of birth control methods for subjects participating in clinical studies: eg, established use of oral, injected or implanted hormonal methods of contraception associated with inhibition of ovulation; placement of an intrauterine device (IUD) or intrauterine system (IUS); male partner sterilization (the vasectomized partner should be the sole partner for that subject); true abstinence (when this is in line with the preferred and usual lifestyle of the subject). A woman of childbearing potential must have a negative serum (β-human chorionic gonadotropin [β-hCG]) at baseline before randomization. A woman must agree not to donate ovocytes for the purposes of assisted reproduction during the study and for 3 months after receiving the last dose of study agent. Note: If the childbearing potential changes after start of the study (eg, woman who is not heterosexually active becomes active, premenarchal woman experiences menarche) that woman must begin a highly effective method of birth control, as described above. A man who is sexually active with a woman of childbearing potential and has not had a vasectomy must agree to use a barrier method of birth control eg, either condom with spermicidal foam/gel/film/cream/suppository or partner with occlusive cap (diaphragm or cervical/vault caps) with spermicidal foam/gel/film/cream/suppository, and all men must also not donate sperm during the study and for 3 months after receiving the last dose of study agent The method of birth control will be clearly documented in patient file. 3. Patients with active PsA according to for ≥6 months, despite ≥3 months of csDMARD therapy, and ≥4 weeks of non-steroidal anti inflammatory drugs (NSAIDs) therapy. 4. At least 1 swollen joint at screening or baseline (despite csDMARD therapy) with ability to perform a synovial biopsy at W0. 5. Patients with newly documented latent TB are eligible provided initiation of appropriate treatment. 6. Concomitant MTX or SSZ is permitted if started ≥3 months prior to study start and at a stable dose (≤25 mg/week for MTX and ≤ 3 g/day for SSZ) for ≥4 weeks. 7. Patients on MTX must be on stable folic acid supplementation before randomization. 8. Concomitant NSAIDs and oral corticosteroids (≤10 mg prednisone/day) are permitted if stable for at least 2 weeks. 9. Allowed concomitant medications are to remain stable through week 24. 10. Patients cannot have previously received any biologic agent 11. DMARDs other than MTX or sulfasalazine (SSZ) must be interrupted. DMARDs other than MTX are not allowed within 4 weeks prior to or during trial participation. A washout period needs to be considered. (8 weeks for leflunomide). 12. At least one joint (small or large) to biopsy in order to get synovial tissue. Small joints must have an US grey-scale score > 2 on Doppler  Patients fulfilling any of the following are not eligible for in this study. 1. Contraindications for needle-arthroscopy such as joint replacement (in the affected knee or ankle joint) or anticoagulation. 2. Use of any investigational drug and/or devices within 4 weeks of baseline, or a period of 5 half-lives of the investigational drug, whichever is longer. 3. Conditions/situations such as: 1. Patients with conditions/concomitant diseases making them non evaluable for the primary endpoint 2. Impossibility to meet specific protocol requirements (e.g. blood sampling) 3. Patient is the Investigator or any sub-investigator, research assistant, pharmacist, study coordinator, other staff or relative thereof directly involved in the conduct of the protocol 4. Uncooperative or any condition that could make the patient potentially noncompliant to the study procedures 4. Any therapy by intra-articular injections (e.g. corticosteroid) within 4 weeks before baseline. 5. Any intramuscular corticosteroid injection within 2 weeks before baseline. 6. Prior treatment with a biologic agent. 7. A history of active tuberculosis (TB)