Persistence of Biologics in the Treatment of Psoriatic Arthritis (Psa): Data From a Large Hospital Based Longitudinal Cohort.

Abstract

To analyze the trends in biologics use at a specialized center over a period of 20 years. We performed a retrospective analysis of 571 patients diagnosed with PsA enrolled at the Toronto cohort who initiated a biologic therapy between January 1, 2000, and July 7, 2020. The probability of drug persistence over time was estimated nonparametrically. The time to discontinuation of first and second treatment was analyzed using Cox regression models, whereas a semiparametric failure time model with a gamma frailty was used to analyze the discontinuation of treatment over successive biologic therapy. When used as a first biologic, the highest 3-year persistence probability was observed with certolizumab, while IL-17i had the lowest probability. However, when used as second medication, certolizumab had the lowest drug survival even when accounting for selection bias. Depression and/or anxiety was associated with a higher rate of drug discontinuation due to all causes (RR 1.68, p= 0.01) while having higher education was associated with lower rates (RR 0.65, p= 0.03). In the analysis accommodating multiple courses of biologics, a higher tender joint count was associated with a higher rate of discontinuation due to all causes (RR 1.02, p=0.01). Older age at start of first treatment was associated with a higher rate of discontinuation due to side effects (RR 1.03, p=0.01) while obesity had a protective role (RR 0.56, p=0.05). Persistence on biologics depends on whether it is the first or second biologic used. Depression/anxiety, higher tender joint count, and older age lead to drug discontinuation.