RT Journal Article SR Electronic T1 4CPS-113 The effectiveness of Janus kinase inhibitors in moderate to severe active rheumatoid arthritis JF European Journal of Hospital Pharmacy JO Eur J Hosp Pharm FD British Medical Journal Publishing Group SP A105 OP A106 DO 10.1136/ejhpharm-2024-eahp.217 VO 31 IS Suppl 1 A1 Martinez-Molina, C A1 Corominas, H A1 Diaz-Torne, C A1 Park, HS A1 Ojeda, S A1 Feliu, A A1 Vidal, S YR 2024 UL http://ejhp.bmj.com/content/31/Suppl_1/A105.2.abstract AB Background and Importance Janus kinase inhibitors (JAKi) are indicated for the treatment of moderate to severe active rheumatoid arthritis (RA). Their mechanism of pharmacological action depends on their competition with adenosine triphosphate (ATP) for the catalytic site of Janus Kinases. ATP levels have been correlated with the systemic cytokine storm induction and inflammation. To date, there is limited real-world data assessing the influence of RA disease activity on the effectiveness of JAKi treatment.Aim and Objectives To evaluate the influence of RA disease activity on the effectiveness of JAKi treatment, within real-world scenarios.Material and Methods This was a retrospective study (2017/09–2023/09) that included all RA patients who were treated with tofacitinib, baricitinib, upadacitinib, or filgotinib at a tertiary hospital.Treatment retentions, for the discontinuation reason of lack of effectiveness, were examined through the Cox model and the Kaplan-Meier estimate. The Cox model was applied to analyse the disease activity as a potential predictive factor that could influence treatment retention. The Disease Activity Score 28-joints using C-Reactive Protein (DAS28-CRP) was considered for measuring disease activity. The Kaplan-Meier estimate was used to evaluate treatment retention curves, with the log-rank test employed for comparison. Statistical analyses were performed utilising STATA software.Results 184 JAKi treatments were included, corresponding to 123 RA patients (86% women, 63±13 years old). At JAKi treatment initiation, RA disease activities were: moderate activity (47.8%) and high activity (52.2%).The Cox model’s analysis indicated that high activity significantly increased the risk of treatment discontinuation due to lack of effectiveness (HR: 1.91; p=0.025). The Kaplan-Meier estimate showed that discontinuation rates due to lack of effectiveness were greater for high activity compared to moderate activity (p=0.022; figure 1).Abstract 4CPS-113 Figure 1 Conclusion and Relevance Our findings suggest statistically significant differences in the influence of high RA disease activity compared to moderate activity on the effectiveness of JAKi treatment. A high activity was significantly linked to an increased risk of treatment discontinuation due to lack of effectiveness.Conflict of Interest No conflict of interest.