AVT04, a Biosimilar to Reference Product Ustekinumab, for the Treatment of Plaque Psoriasis: Insights from a Real-World Experience up to 28 Weeks

Introduction: This study aims to evaluate the real-life efficacy and safety of a biosimilar to reference product (RP) ustekinumab for the treatment of plaque psoriasis in different patient scenarios. The cohort included ustekinumab-switched patients, who switched from the RP to the biosimilar, and ustekinumab-naïve patients, never treated with ustekinumab. Ustekinumab-naïve patients were subdivided into bio-naïve (no prior biologic therapy) and bio-experienced (previous non-ustekinumab biologic therapy). Methods: Adult patients with chronic plaque psoriasis treated with AVT04 were followed up to 28 weeks. Efficacy of the biosimilar was assessed by improvement of the Psoriasis Area Severity Index (PASI) 75, 90, and 100 responses from baseline to weeks 16 and 28. A cost-minimisation analysis over a 1-year time horizon was performed to estimate costs and potential savings with AVT04 versus RP across the Italian National Health Service (NHS). Results: Throughout the observation period, a sustained improvement in PASI was observed in the overall cohort of 183 patients, encompassing both the ustekinumab-switched and ustekinumab-naïve groups. Within the ustekinumab-naïve group, a trend toward more favourable PASI 75/90/100 responses was observed in bio-naïve patients compared to bio-experienced patients. By 28 weeks of treatment, a higher proportion of bio-naïve patients compared to the bio-experienced group achieved PASI 75 (72.7% vs. 56.2%), PASI 90 (72.7% vs. 50.0%), and PASI 100 (54.5% vs. 37.5%), respectively (p > 0.05). No adverse events were reported during the study. Furthermore, the cost-minimisation analysis suggested that compared to the RP, AVT04 has the potential to generate approximately €5200 in annual savings per patient for the Italian NHS, representing around €20 million in nationwide savings. Conclusion: AVT04 biosimilar shows consistent efficacy results in both ustekinumab-switching and ustekinumab-naïve patients, supporting its integration into real-world practice as an effective and cost-saving therapeutic option. Further studies are warranted to confirm and expand these preliminary findings across a broader bio-naïve cohort.