Background: Switch patterns among different biologics and from originators to biosimilars (and vice versa) can be complex in patients with psoriasis (PsO) and psoriatic arthritis (PsA).
Objective: The aim of this study was to describe switching patterns of biological drugs in PsO/PsA patients and to explore predictors of multiple switches and switch-back.
Research design and methods: A large-scale retrospective cohort study was conducted using the Italian VALORE database. Bio-naïve users treated for PsO/PsA during 2010-2022 were included. Time to switch/swap and predictors of multiple switches and switch-back were analyzed.
Results: Thirty-thousand seven hundred bio-naïve users were included. At 3 and 5 years of follow-up, patients with at least one switch/swap were 37.1% and 47.8%, respectively. The median time to first switch/swap was significantly shorter (p< 0.001) for TNF-α inhibitors (2,068 days) than anti-IL (2,780 days). At 1 year of follow-up patients starting with IL-23 switched/swapped biological therapy less frequently than those with anti-IL-12/23 and anti-IL-17 (4.9% vs. 8.7% and 9.4%, respectively). Patients starting with anti-IL-12/23 reported a significantly lower risk of multiple switches and switch-back (0.74, 95% CI, 0.67-0.83; 0.58, 95% CI, 0.44-0.77, respectively) than those with TNF-α inhibitors.
Conclusions: Patients with PsO/PsA starting with TNF-α inhibitors switch/swap more rapidly and frequently than those with anti-IL, which are also associated with a reduced risk of multiple switches during follow-up.
Keywords: Biologics; biosimilars; psoriasis; psoriatic arthritis; switch; switch-back.