Phase 2 Trial of FT2109 for the Treatment of Psoriatic Arthritis

This study will investigate if the study medicine FT2109 can treat symptoms of active Psoriatic Arthritis (PsA). This study assesses the safety and efficacy of FT2109 in adult participants with active PsA who may or may not have been treated previously with advanced therapy and who may be on stable background therapy. In this study, researchers will look at different doses of FT2109 compared to placebo (a treatment with no active study drug in it). Researchers will try to learn if at least one of the study doses of FT2109 works better than placebo to treat PsA symptoms.

Inclusion Criteria: * Age 18-75 years * Body mass index (BMI) within the range 18 to 40 kg/m2 * Diagnosed with PsA for ≥6 months, and meeting Classification Criteria for Psoriatic Arthritis (CASPAR) at screening * Have active PsA: ≥3 tender joints and ≥3 swollen joints at screening and baseline and having hsCRP \>0.3 mg/dL (3 mg/L) * Having active plaque psoriasis (≥1 lesion ≥2cm) or nail psoriasis at screening * Biologic disease modifying anti-rheumatic drug (bDMARD) or targeted synthetic DMARD (tsDMARD) experienced participants can have received (a) up to one bDMARD (excluding TNF and IL-17 targeting therapies), and (b) up to one tsDMARD (excluding JAK targeting therapies) * bDMARD or tsDMARD naïve participants must have failed (a) at least one but no more than two csDMARDs AND/OR (b) Apremilast Exclusion Criteria: * Presence of other inflammatory or autoimmune conditions, including but not limited to rheumatoid arthritis, primary ankylosing spondylitis or non-radiographic axial spondyloarthritis without psoriasis, systemic lupus erythematosus, drug-induced dermatosis, inflammatory bowel disease, or Lyme disease * Current non-plaque forms of psoriasis (e.g., erythrodermic, guttate, or pustular psoriasis) * Use of \>10mg/day prednisone equivalent or change in oral glucocorticoid dosage within 4 weeks prior to Baseline * Received targeted intra-articular, trigger point, tender point, intra-bursa, or intra-tendon sheath surgical or pharmacological treatment within 8 weeks of the Screening Visit * Undergone surgical treatment for PsA including synovectomy and arthroplasty in more than 3 joints and/or within the last 12 weeks prior to the Screening Visit.