Background and Importance Different JAK inhibitors (JAKi) are recently marketed at Spain for the treatment of rheumatoid arthritis (RA). However, there is little data about their persistence when a previous JAKi has been used on RA treatment, which could influence pharmacotheraphy with these drugs.

Aim and Objectives To analyse the persistence to treatment with a second JAKi treatment in RA patients which have previously been treated with a first JAKi.

Material and Methods Observational, retrospective study including all patients with RA treated with more than one JAKi until August 31, 2022. Demographic variables, median disease duration, median time on treatment (mToT) of JAKis including causes of end of treatment (loss of effectiveness or adverse reaction). Persistence was measured through mToT.

Results 18 patients (16 women), median age of 48 years [interquartile range (IQR):40–55] were included. Median time from diagnosis 9.4 years (IQR:6.3–11.8). Concomitant treatment: methotrexate (n=7) or leflunomide (n=2). Before first JAKi treatment, 12 patients were treated previously with at least a biologic disease-modifying antirheumatic drug (bDMARD). 4 patients were treated with at least a bDMARD after finishing first JAKi, rest of patient switched directly to another second JAKi.

Total mToT with the first JAKi: 12.1 months (IQR:3.3–31.3). Causes of end of treatment: loss of effectiveness (n=11; mToT: 15.7 months, IQR:11.9–35.3) and adverse effects (n=6; mToT: 2.5 months, IQR:1.4–4.7); a patient changed JAKi treatment due to cardiovascular risk.

Among patients who finished first JAKi due to loss of effectiveness (n=11), mToT with second JAKi was 9.6 months (IQR:4.1 -14.2; 6/11 continue treatment; 1/11 loss of follow-up). Considering only patients who finished both first and second JAKi due to loss of effectiveness (n=4), mToT was 12.5 months (IQR: 8.0 -17.7) vs 6.6 (IQR:3.1–16.1) respectively.

33% of patients (2/6) who finished first JAKi treatment because of adverse effects did not tolerate neither the second JAKi (mToT: 2.5 months, IQR:1.4–140; 3/6 continue treatment).

Conclusion and Relevance Persistence is higher with first JAKi when treatment with both first and second JAKi finished due to loss of efficacy, however data is still immature. Patients who do not tolerate treatment with a first JAKi seems to have a higher chance of not tolerating a second JAKi.

Conflict of Interest No conflict of interest