Analysis of the Pharmacoutilization of Biological Drugs in Psoriatic Arthritis Patients: A Real-World Retrospective Study Among an Italian Population

Abstract

Introduction: Real-world pharmacoutilization analysis of biological drugs in psoriatic arthritis (PsA) patients with the aim to evaluate biologic treatment patterns and pharmacoutilization among patients with PsA in Italy.

Methods: A retrospective study was conducted using administrative databases of Italian Entities. PsA patients were included and diagnosed by hospitalization and/or an active exemption code. Two analyses were performed: a cross-sectional for treatment patterns in patients enrolled among 2017-2020, and a longitudinal study during 2015 to investigate the pharmacoutilization, in terms of persistence and monthly maintenance dosage of biological/targeted synthetic disease-modifying antirheumatic drugs (b/tsDMARDs). Patients with or without b/tsDMARDs prescriptions before inclusion were defined as bioexperienced or naïve, respectively. An analysis on ixekizumab-treated patients (IXE patients) from the 2017-to study ending was performed.

Results: PsA was diagnosed in 24,786 (2017), 27,221 (2018), 28,889 (2019), and 29,292 (2020) patients. Across 2017-2020, 31.1-40.5% of PsA patients were untreated with systemic medications, and 16.4-18.8% were under biological therapies. Among b/tsDMARD-treated patients, decreasing use of TNF-inhibitors (77.6-57.1%) and increasing IL-inhibitors (19.6-33.2%) was found across 2017-2020, respectively. Persistence to TNF-inhibitors and IL inhibitors as first-line ranged, respectively, 74.9-83.0% and 73.0-84.6%; specifically, 73.1-76.9% and 73.0-83.8% among bio-naïve, 83.3-90.0%, and 87.0% among bio-experienced. Among IXE-patients (N = 178), 55.6% were bio-naïve, while 21.9% previously used secukinumab, 12.9% adalimumab, 10.1% etanercept. During a 1-year follow-up, 6.8% of IXE patients switched therapy.

Conclusions: This real-world study of PsA pharmacoutilization in Italy showed that more than one-third of patients were systemically untreated, and almost 20% were receiving biological medications. Among biological users, increasing use of IL-inhibitors and a decrease in TNF-inhibitors prescriptions over the years were found. A rather-high extent of persistency in treatment was observed. A focused analysis on IXE patients revealed over half of them to be bio-naïve, while around one-fourth were bio-experienced to IL inhibitors.

Keywords: Biologic DMARD; Pharmacoutilization; Psoriatic arthritis; Real-world study.

Fig. 1

Treatment patterns among the PsA patients. During the first year after inclusion (index-date included), the percentage of patients untreated with systemic medication for PsA, treated with csDMARD/NSAIDs or with b/tsDMARDs for each calendar year is reported. *partial data available (analysis on databases with a complete recording of 2020)

Fig. 2

Analysis of the b/tsDMARD treatment patterns in the PsA patients. At the index-date, in overall (A), bioexperienced (B), and bionaïve (C) patients, the percentage of those treated with TNF inhibitors, IL inhibitors or tsDMARD is reported per each calendar year. The number of analyzed patients (N) is also reported for each year. *partial data available (analysis on databases with a complete recording of 2020)