Background Although existing data support the effectiveness of the low dose regimen (LDR, 1gr every 6 months) of rituximab as initial treatment for active rheumatoid arthritis (RA) (2), it is unknown whether this regimen may be used to maintain the therapeutic effect in patients achieved clinical remission or low disease activity (LDA) upon treatment with conventional rituximab regimen (2gr every 6 months)

Objectives To evaluate the effectiveness of the rituximab LDR for maintenance of clinical remission and/or LDA in patients with RA in clinical practice.

Methods Long-term prospective study of RA patients who received rituximab in the Rheumatology Department of the University Hospital of Heraklion during 03/2005–07/2016. All patients on clinical remission [DAS 28 (ESR) <2.6] or LDA [DAS28 (ESR) <3.2] for at least 12 months were treated with the LDR after obtaining verbal consent.

Results We analyzed 247 patients who received conventional rituximab regimen, of median age (IQR) 62 (54.3–70.4)years, females (84%), disease duration 9.6 (5.6–18.3) years,52% seropositive (RF or anti-CCP). Patients have had failed in (median) 3 (2–3) non-biologic (nbDMARDs) and 1 (1–2) biologic DMARDs (bDMARDs) before rituximab initiation. At baseline of rituximab treatment, 58.3% and 91.1% of them were on steroids and (nbDMARDs) respectively, while the disease activity was high [mean DAS28 (ESR): 5.84 (5.20–6.49)] and they had impaired physical functioning [mean HAQ: 1.0 (0.63–1.38)].

Overall, 27/247patients (11%) received the LDR. Before the initiation of LDR, the duration of rituximab treatment was 24 (18–48) months and cumulative rituximab “exposure” was 8 (6–15) gr. At the time of LDR initiation, disease activity [DAS28 (ESR)] was 2.8 (2.2–3.6) and HAQ: 0 (0–0.4), while the time needed for achieving remission or LDA was18 (8–23) months. The median duration of follow-up of patients on LDR was12 (6–20) months. 23 (85%) of patients remained in remission or LDA with median DAS28 (ESR) 2.85 (2.23–3.52) and HAQ 0 (0–0.5) at last follow-up. Only 3 (11%) of the patients experienced an increase of DAS28 (>1.2) and 2 (7%) of patients return to conventional dose.

Conclusions In clinical practice, RA patients who achieved remission or low disease activity with conventional dose of rituximab may sustain clinical responses if treated with LDR. These preliminary findings support the use of LDR as maintenance treatment regimen and this may allow cost savings. (1)

References

1. Gianfranco Ferraccioli et al.Could we use a lower dose of rituximab to treat rheumatoid arthritis in clinical practice: pros and cons? Arthritis Res Ther. 2016; 18: 126.

2. Chatzidionysiou K, et al. Effectiveness of two different doses of Rituximab for the treatment of rheumatoid arthritis in an international cohort: data from the CERERRA collaboration. Arthritis Res Ther. 2016; 18:50.

References

Disclosure of Interest None declared