psoriatic arthritis

Overview

Psoriatic arthritis (PsA) is a chronic, immune-mediated inflammatory arthritis occurring in association with psoriasis, a common skin condition characterized by erythematous, scaly plaques. PsA belongs to the broader category of spondyloarthropathies and manifests with a heterogeneous clinical picture encompassing peripheral joint inflammation, enthesitis, dactylitis, axial involvement, and nail disease. Collectively, psoriasis and PsA are increasingly recognized as a unified systemic condition termed "psoriatic disease" (PsD), reflecting shared pathogenic mechanisms and immunological underpinnings. The disease predominantly involves dysregulation of the innate and adaptive immune systems, with key pro-inflammatory cytokines — including tumor necrosis factor (TNF), IL-17A, and IL-23 — driving synovial inflammation, bone remodeling, and cutaneous manifestations. Cardiometabolic comorbidity is a well-established concern in the PsA population, contributing to overall disease burden and influencing treatment decisions.

The pathogenesis of PsA is driven by activated T-cell subsets, dendritic cells, and macrophages operating within inflamed synovium and skin. Dysregulated production of anti-inflammatory cytokines, impaired regulatory T-cell activity, and activated innate lymphoid cells collectively sustain chronic inflammation. Patients with psoriasis carry a substantially elevated risk of developing PsA over their lifetime, making early identification and biologic intervention a central research priority. The therapeutic landscape for PsA has expanded considerably, encompassing TNF inhibitors such as adalimumab, etanercept, and infliximab; the IL-17A inhibitor ixekizumab; the IL-12/23 inhibitor ustekinumab; selective IL-23 inhibitors such as guselkumab; and the phosphodiesterase-4 (PDE4) inhibitor apremilast — each targeting distinct nodes in the inflammatory cascade.

Focus of Latest Publications

Recent publication activity surrounding psoriatic arthritis has been dominated by real-world evidence on biologic and small-molecule therapies, pharmacovigilance investigations, immunological mechanistic studies, and population-level risk analyses.

Biologic therapy effectiveness and persistence have been central themes. A multicenter retrospective real-world study from Argentina (PMID 42154041) evaluated the effectiveness and 12-month persistence of IL-23 inhibitors in PsA, finding high persistence rates and supporting their use in populations where randomized trial data were previously scarce. Similarly, a multicenter Italian real-world study (PMID 42230809) examined guselkumab in PsA patients, exploring six-month clinical predictors of achieving DAPSA (Disease Activity in Psoriatic Arthritis) remission at 12 months, with real-world evidence confirming outcomes consistent with randomized trial data. The real-world efficacy and safety of ixekizumab, an IL-17A inhibitor, was assessed in a joint psoriasis and PsA clinic setting (PMID 41632820), where both articular and cutaneous response outcomes were evaluated in patients with chronic inflammatory disease affecting quality of life, including those with difficult-to-treat anatomical areas.

Apremilast, an oral PDE4 inhibitor, was the focus of the multicenter Italian MAPSI II study (PMID 42247059), which assessed its effectiveness and safety in PsA across multiple rheumatology centers in a real-world setting. A complementary immunological study (PMID 42089905) investigated the mechanism underlying apremilast's effects, reporting that apremilast therapy increases the proportion of CD39+CD4+ T cells in the peripheral blood of patients with psoriatic disease — a finding with potential implications for immunoregulatory pathways in PsA.

Infection risk and pharmacovigilance were addressed in a target trial emulation study utilizing the Italian VALORE distributed database network (PMID 42019563), which compared the risk of serious infections across biological drugs used in PsO and PsA, with particular attention to long-term exposure and older adult populations. These findings are clinically relevant given the immunosuppressive nature of biologics and the vulnerability of the PsA patient population to infectious complications.

Treatment with ustekinumab, an IL-12/23 blocker, is approved for treating moderate to severe plaque psoriasis, PsA, Crohn's disease, and ulcerative colitis (PMID 42212686), underscoring the shared inflammatory pathways across immune-mediated diseases and the broad clinical utility of targeting the IL-23 axis.

Immunological biomarkers were explored in a prospective comparative case-control study (PMID 41848948) that evaluated serum TWEAK (TNF-like weak inducer of apoptosis) levels and treatment response in patients with psoriasis and PsA receiving adalimumab or methotrexate. This study contributed to the understanding of systemic biomarkers in chronic immune-mediated diseases with systemic impact.

Epidemiological and prevention-oriented research was represented by a population-based cohort study (PMID 42097693) examining how biologic drug class and treatment line in psoriasis patients influences the subsequent risk of developing PsA, confirming the established epidemiological relationship between psoriasis and PsA progression. A retrospective single-center study from Israel on guttate psoriasis (PMID 42183773) further examined the association between this psoriasis subtype and systemic comorbidities including PsA and metabolic syndrome.

Physical activity as an adjunct intervention in PsA was addressed in a longitudinal observational study (PMID 42160326) that followed patients with spondyloarthritis, PsA, and rheumatoid arthritis referred for adapted physical activity programs, examining long-term adherence over a multi-year follow-up period.

Key Publications

• Jun Real-world effectiveness and safety of apremilast in psoriatic arthritis: results from the multicenter Italian MAPSI II study. (Clinical rheumatology, 2026, PMID 42247059): "To assess the effectiveness and safety of apremilast in the treatment of psoriatic arthritis (PsA) in a real-world setting across multiple rheumatology centers in Italy."
• Jun Six months predictors of DAPSA Remission With Guselkumab in Psoriatic Arthritis in a Multicenter Real-World Study. (Scientific reports, 2026, PMID 42230809): "Real-world evidence on 12-month outcomes of guselkumab (GUS) in psoriatic arthritis (PsA) remains limited."
• Jun Prostate cancer mortality among men with and without comorbidity: Long-term results from the European randomized study of screening for prostate cancer Rotterdam. (European journal of cancer (Oxford, England : 1990), 2026, PMID 41997039): "Prostate-specific antigen (PSA)-based prostate cancer (PCa) screening can be improved by individualised, risk-stratified strategies."
• Jun Phase 1b trial of Bavdegalutamide (ARV-110) in combination with Abiraterone for metastatic prostate cancer. (Clinical cancer research : an official journal of the American Association for Cancer Research, 2026, PMID 42227954): "...in patients with mPC experiencing prostate-specific antigen (PSA) progression on abiraterone."
• Jun Impact of the Nadir Androgen Receptor Signaling Inhibitor-Derived Integrative Response Model in Real-World Patients With Metastatic Castration-Sensitive Prostate Cancer. (The Prostate, 2026, PMID 42018551): "Early deep prostate-specific antigen (PSA) decline after the initiation of androgen receptor signaling inhibitor (ARSI) therapy is associated with favorable long-term outcomes in metastatic castration-sensitive prostate cancer (mCSPC)."
• Jun PSA Response as a Prognostic Factor of Overall Survival in Patients with Metastatic Hormone-sensitive Prostate Cancer Treated with Apalutamide: Real-world Evidence. (European urology open science, 2026, PMID 42058872): "Prostate-specific antigen (PSA) decline has been proposed as a prognostic marker in metastatic hormone-sensitive prostate cancer (mHSPC)."
• Jun Predictive Role of PSA Kinetics in Oncological Outcomes of Metastatic Castration-sensitive Prostate Cancer. (Anticancer research, 2026, PMID 42203328): "However, the prognostic value of prostate-specific antigen (PSA) kinetics in real-world settings remains unclear."
• Jun Robotic-assisted radical prostatectomy using the Toumai system: initial single-center experience in Morocco. (Journal of robotic surgery, 2026, PMID 42223781): "Median preoperative PSA was 6.4 ng/ml (IQR: 5.3-8.7)."
• Jun Comparative risk of serious infections across biological drugs in patients with psoriatic arthritis or psoriasis: A target trial emulation using the Italian VALORE distributed database network. (Pharmacological research, 2026, PMID 42019563): "Risk of serious infections with biological drugs for psoriasis (PsO) and psoriatic arthritis (PsA) remains uncertain, particularly with long-term exposure and in older adults."
• May Human factors validation study of a disposable autoinjector (Bmab 1200 autoinjector) for subcutaneous delivery of Ustekinumab. (Drug delivery, 2026, PMID 42212686): "Ustekinumab is approved for treating moderate to severe plaque psoriasis, psoriatic arthritis, Crohn's disease, and ulcerative colitis."