FRI0212 Is there a downside in off-label use of rituximab? - 2-year data from the german biologics register rabbit.

Background Since 2006, rituximab (RTX) is approved in combination with methotrexate (MTX) for the treatment of rheumatoid arthritis (RA) after failure of tumor necrosis factor-α (TNFα) blocking therapy. A substantial number of patients, especially among those with severe disease, do not tolerate methotrexate and/or other synthetic DMARDs. Therefore off-label useof RTX in monotherapy or with leflunomide(LEF) is common in daily practice but rarely investigated. Objectives We compared treatment regimens with RTX+MTX, RTX+LEF or RTX monotherapy regarding safety and effectiveness in a 2-year follow-up, taking discontinuation rates, drop-outs and concomitant use of glucocorticoids into account. MethodsWe included patients enrolled in the German biologics register RABBIT between 2007 and 2011 with a minimum of one follow-up visit (N=709). Therapy discontinuation and drop-out processes were examined in Cox-proportional hazard models. Linear mixed effects models were applied to capture the influence of concomitant use of glucocorticoids and of clinical effectiveness, measured by the disease activity score (DAS28). We applied multiple imputation techniques to address missing data. Results Patients of all treatment variants showed similar clinical baseline characteristics except for a reduced functional capacity (FFbH, p Conclusions Off-label usesof RTX in combination with LEF or of RTX in monotherapy are not inferior to RTX+MTX therapy regarding safety, effectiveness and therapy adherence. RTX+LEF or RTX monotherapy are useful alternatives for patients being intolerant to MTX, with the particular feature that RTX monotherapy should be restricted to rheumatoid factor positive patients to ensure therapy adherence. Disclosure of Interest : A. Richter Grant/research support from: Supported by a joint, unconditional grant from AbbVie, Bristol-MyersSquibb, MSD SHARP & DOHME, Pfizer, Roche, and UCB., A. Strangfeld Grant/research support from: Supported by a joint, unconditional grant from AbbVie, Bristol-MyersSquibb, MSD SHARP & DOHME, Pfizer, Roche, and UCB., P. Herzer: None Declared, E. Wilden: None Declared, A. Bussmann: None Declared, J. Listing Grant/research support from: Supported by a joint, unconditional grant from AbbVie, Bristol-MyersSquibb, MSD SHARP & DOHME, Pfizer, Roche, and UCB., A. Zink Grant/research support from: Supported by a joint, unconditional grant from AbbVie, Bristol-MyersSquibb, MSD SHARP & DOHME, Pfizer, Roche, and UCB.