Apremilast Retention Rate in Clinical Practice: Observations from an Italian Multi-center Study

Objective: There are few real-world setting studies focused on apremilast effectiveness (i.e., retention rate) in psoriatic arthritis (PsA). The main aim of this retrospective observational study is the assessment of apremilast 3-year retention rate in real-world PsA patients. Moreover, the secondary objective is to report the reasons of apremilast discontinuation and the factors related to treatment persistence.

Methods: In fifteen Italian rheumatological referral centers, all PsA consecutive patients who received apremilast were enrolled. Anamnestic data, treatment history, and PsA disease activity (DAPSA) at baseline were recorded. The Kaplan-Meier curve and the Cox analysis computed the apremilast retention rate and treatment persistence-related risk factors. A p-value < 0.05 was considered statistically significant.

Results: The 356 enrolled patients (median age 60 [interquartile range IQR 52-67] yrs; male prevalence 42.7%) median observation period was 17 [IQR 7-34] months (7218 patients-months). The apremilast retention rate at 12, 24, and 36 months was, respectively, 85.6%, 73.6%, and 61.8%. The main discontinuation reasons were secondary inefficacy (34% of interruptions), gastro-intestinal intolerance (24%), and primary inefficacy (19%). Age and oligo-articular phenotype were related to treatment persistence (respectively hazard ratio 0.98 IQR 0.96-0.99; p = 0.048 and 0.54 IQR 0.31-0.95; p = 0.03).

Conclusion: Almost three-fifths of PsA patients receiving apremilast were still in treatment after 3 years. This study confirmed its effectiveness and safety profile. Apremilast appears as a good treatment choice in all oligo-articular PsA patients and in those ones burdened by relevant comorbidities. Key Points • Apremilast retention rates in this real-life cohort and trials are comparable. • The oligo-articular phenotype is associated with long-lasting treatment (i.e., 3 years). • No different or more prevalent adverse events were observed.