Background: Janus kinase inhibitors (JAKi) are effective treatments for chronic inflammatory arthritis (CIA). Tofacitinib and baricitinib are pan-JAK inhibitors, while upadacitinib and filgotinib are JAK1-selective inhibitors.
Objective: This study aimed to compare retention rates between JAKi classes and identify predictors of discontinuation.
Design: Retrospective observational study.
Methods: We retrospectively evaluated patients with CIA (Rheumatoid Arthritis (RA), Psoriatic Arthritis (PsA), and Spondyloarthritis (SpA)) treated with JAKis from 2017 to 2024. The independent variable was JAKi class (pan-JAK inhibitors/JAK1-selective inhibitors). Retention was assessed using Kaplan-Meier estimates, and predictors of discontinuation were evaluated through Cox multivariable regression.
Results: The study included 181 patients (83% women; median age 56). Diagnoses were RA (84%), PsA (9%), and SpA (7%). A total of 227 JAKi treatment courses were analyzed: 96 JAK1-selective inhibitors and 131 pan-JAK inhibitors. Overall, 118 courses (52%) were discontinued (55% inefficacy; 42% adverse events). The discontinuation incidence rate (IR) was 35.5 per 100 patient-years, with 50% stopping treatment within 1.65 years. Discontinuation was more frequent in women, patients with cardiovascular (CV) disease or risk factors, and in PsA compared to RA. Discontinuation rates were lower for JAK1-selective inhibitors (IR: 28.6; 95% confidence interval (CI): 20.5-39.8) versus pan-JAK inhibitors (IR: 39.6; 95% CI: 31.9-49.1). Multivariate analysis confirmed that pan-JAK inhibitors, female sex, PsA, CV disease, prior targeted biological and synthetic disease-modifying drugs exposure, and leflunomide co-treatment increased the risk of discontinuation.
Conclusion: Pan-JAK inhibitors may have higher discontinuation rates than JAK1-selective inhibitors in real-world CIA patients. Clinical characteristics and comorbidities should guide JAKi selection to optimize long-term treatment retention.
Keywords: Janus kinase inhibitors; chronic inflammatory arthritis; drug retention.
Comparative study of the duration of different drugs, called Janus kinase inhibitors, to reduce inflammation in patients with chronic inflammatory arthritis This study looked at how long patients with chronic inflammatory arthritis (CIA) continue to take a type of drug called a Janus kinase inhibitor (JAK inhibitor or JAKis). These drugs help reduce inflammation in diseases such as rheumatoid arthritis (RA), psoriatic arthritis (PsA), and spondyloarthritis (SpA). There are two types of JAKis: a) Pan-JAK inhibitors, like tofacitinib and baricitinib b) JAK1-selective inhibitors, like upadacitinib and filgotinib The researchers reviewed the medical records of 181 people treated with JAKis between 2017 and 2024. Most of the patients were women, with a mean age of 56 years, and most had RA. The researchers studied how often patients stopped taking these medications, and the reasons for stopping. They found that about half of the treatments were stopped, mostly due to lack of effectiveness (the drug did not work well enough) or side effects. People were more likely to stop treatment if they had other health problems, like heart disease, or if they had PsA instead of RA. Notably, patients remained on treatment longer with selective JAK1 inhibitors than with pan-JAK inhibitors. Those who were female, had prior treatment or were also taking a drug called leflunomide were more likely to stop treatment early. In summary, this study demonstrates that not all JAKis work the same in all people. Rheumatologists must consider the health status of each patient when choosing the most appropriate treatment.
© The Author(s), 2025.