Predictors of ineffective therapy in patients with rheumatoid arthritis requiring bDMARDs/JAKi switching: data from a single-center prospective study

Background. In rheumatoid arthritis (RA) the treatment target of remission or low disease activity is achieved in only 50–60% of patients, even with the use of modern targeted therapies, such as biological disease-modifying antirheumatic drugs (bDMARDs) and Janus kinase inhibitors (JAKi). The failure of a bDMARD or JAKi necessitates switching to another treatment of these classes. However, the factors influencing the treatment effectiveness after such a switch remain unknown. Aim. To identify factors associated with poor response when switching bDMARDs/JAKi in RA patients whose previous bDMARDs/JAKi were also ineffective. Materials and methods. A total of 164 patients with RA, 46.5±14 years old, 86.6% female, RF '+' 76.8%, with Disease Activity Score – DAS283.2, who had failed prior bDMARD/JAKi therapy requiring a switch were enrolled. DAS28-CRP was assessed 6 months after induction of new bDMARDs/JAKi therapy. Patients with moderate/high RA activity (DAS28-CRP3.2) were classified as non-responders (group 1), patients in remission/ low disease activity were classified as responders (group 2). Factors associated with poor response to therapy when switching bDMARDs/JAKi were identified, and then a predictive model was formed by binary logistic regression. Results. Group 1 included 80 (48.8%) patients and group 2 included 84 (51.2%) patients. Group 1 showed statistically significantly higher body mass index (BMI), later age of onset of RA, less advanced radiological stage, baseline greater TJC (tender joint count) and SJC (swollen joint count), more severe PtPGA and PhPGA, higher DAS28-CRP, CDAI and SDAI, higher PainDetect, HADS depression, FSS, CSI, FiRST, FACIT-F, higher BPI pain (for all parameters p0.05). A regression model for bDMARD/JAKi switching ineffectiveness with a sensitivity of 77.5% and specificity of 70.2% included BMI, RF seronegativity, CSI, PainDetect numeric score (signs of neuropathic pain), BPI (mean pain) and GC intake at baseline. Conclusion. Initial higher RA activity, pain severity, BMI, signs of central sensitisation and psychoemotional disturbance, and need for GC are associated with a poor response to therapy when switching bDMARDs/JAKi.