JANUS KINASE INHIBITORS IN THE TREATMENT OF RHEUMATOID ARTHRITIS - A LITERATURE REVIEW

Dawid Nowicki; Paulina Małyszczak; Małgorzata Muszyńska; Sylwia Mroszczyk; Katarzyna Karaś Karaś

doi:10.31435/ijitss.1(49).2026.4875

Authors

Dawid Nowicki University Clinical Hospital No. 1, named after Professor Tadeusz Sokołowski of the Pomeranian Medical University in Szczecin, Szczecin, Poland https://orcid.org/0009-0005-2396-3461
Paulina Małyszczak Independent Complex of Public Outpatient Healthcare Facilities in Piaseczno, Piaseczno, Poland https://orcid.org/0000-0002-4537-970X
Małgorzata Muszyńska Lower Silesian Center of Oncology, Pulmonology and Hematology in Wrocław, Wrocław, Poland https://orcid.org/0009-0008-4011-4631
Sylwia Mroszczyk Provincial Specialist Hospital named after Cardinal Stefan Wyszyński in Lublin, Lublin, Poland https://orcid.org/0000-0003-2395-482X
Katarzyna Karaś Karaś Non-Public Health Care Center “Cor” Medical Clinic, Wieruszów, Poland https://orcid.org/0009-0008-1665-6780

DOI:

https://doi.org/10.31435/ijitss.1(49).2026.4875

Keywords:

Rheumatoid Arthritis, Rheumatology, Arthritis, Janus Kinase

Abstract

Rheumatoid arthritis (RA) is a chronic autoimmune disease characterised by persistent joint inflammation, leading to their destruction and deformities. The disease may also manifest with extraarticular symptoms. The pathogenesis of RA is multifactorial, involving genetic, environmental, and immunological factors. Treatment includes disease-modifying antirheumatic drugs, glucocorticosteroids, nonsteroidal anti-inflammatory drugs, biologic TNF-α inhibitors, and janus kinase (JAK) inhibitors. The objective of this study is to present the characteristics of JAK inhibitors, their mechanisms of action, efficacy, and safety. A literature review was conducted using PubMed, Cochrane, Medline, and Google Scholar databases. Data on clinical efficacy, safety profile, and tolerability of tofacitinib, baricitinib, upadacitinib, and filgotinib were collected and analysed. JAK inhibitors block the JAK-STAT pathway, inhibiting pro-inflammatory cytokine signalling. Treatment with tofacitinib, baricitinib, upadacitinib, and filgotinib led to rapid symptom improvement, reduced joint damage, and enhanced quality of life. JAK inhibitors have shown efficacy in patients with methotrexateresistant RA. Adverse effects include infections, gastrointestinal disturbances, and hypercholesterolemia. These drugs can be used as monotherapy or in combination with standard treatment. JAK inhibitors provide an effective and safe alternative for patients with moderate to severe RA who have an inadequate response to other therapies. Treatment with these drugs results in rapid clinical improvement, limits progression of joint damage, and improves patients’ quality of life, representing a modern treat-to-target therapeutic strategy.

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