Drug Retention Rate of Tocilizumab in Uveitis. Real-World Data from the Spanish Biotherapies in Uveitis (BioÚvea) Study Group

Abstract

Purpose : To study drug retention rate (DRR) of tocilizumab (TCZ) in real-world uveitis practice.

Methods : Multicentric, ambispective, observational study of patients treated with TCZ for uveitis. From Nov 2016 to Nov 2017. Demographic and clinical data, timing and reasons for discontinuation, if occurred, were recorded in an electronic encrypted standardized data-base. We performed a multivariate Cox proportional random model in order to identify factors related with discontinuation. For this model, demographic and clinical data were included as independent variables and DRR was included as time-dependent variable. The estimate of censored data was performed using the Kaplan-Meier method. Results were expressed in hazard ratio (HR) and 95% confidence intervals.

Results : 60 patients were analyzed, 65% females. Median age was 34 (IQR 22.7) years. Uveitis was bilateral in 86.6%. Posterior and panuveitis accounted for 60%. TCZ was given as a first biologic line in 13.3%, as a second line in 40% and as a ≥3th line in 46.6%. DRR at 12, 24 and 60 months was 66.6%, 58.34% and 10%, respectively. Median drug retention time (DRT) was 2.4 (IQR 2.6) years. TCZ was discontinued in 32 (53.3%) patients. Discontinuation was due to sustained quiescence in 13.3%, lack of efficacy in 20% and to an adverse event in 16.6% of all included patients. Recorded adverse events included: Infections in 6.6% and cytopenia in 3.3%. Neoplasms, CNS demyelinating diseases or secondary autoimmune diseases were not recorded. Concurrent DMARDs were given to 32 (53.3%) patients. We did not find DRR differences depending on anatomic or etiologic subtype, the use of concurrent DMARDs, previous intra/periocular injections of corticosteroids nor if TCZ was initiated as a first, second or ≥3th biotherapy line. The only factor found to be predictive of TCZ discontinuation was the concurrent use of >7.5mg/d of oral prednisone (HR 11.71, 95%CI 3.0-45.91, p<0.001).

Conclusions : Although TCZ is usually reserved as a 2nd or more biotherapy line in uveitis, its median DRT was 2.4 (IQR 2.6) years, with an acceptable safety profile in this context. Concurrent DMARDs do not seem to extend the period of treatment or determine withdrawal of TCZ in uveitis. The need of ≥7.5mg/d of oral prednisone during TCZ treatment is a predictive factor for its discontinuation.

This abstract was presented at the 2019 ARVO Annual Meeting, held in Vancouver, Canada, April 28 - May 2, 2019.