The use of biological and biosimilar drugs in Rheumatology and Dermatology: analysis of two prescribing centers in Sicily from 2019 to 2020

SUMMARY
Two position papers from the Italian Medicine Agency (AIFA) and the recent (September 2022) statement by European Medicines Agency (EMA) highlighted that biosimilar medicines approved in the European Union (EU) are interchangeable with their reference medicine or with an equivalent biosimilar. AIFA statements assessed that biosimilars must be preferred both for naïve patients and patients already under treatment with biological medicines, for whom it is possible to apply the switch to the biosimilar products. Accordingly, the Sicilian Regional Health Systems has issued different acts to comply with the National directives, and to spread the use of biosimilars products.
This research aimed to evaluate the appropriateness of biosimilars prescriptions by two prescribing centers in Sicily. Specifically, the research was carried out during 2021, analyzing the prescription forms of the biological or biosimilar medicinal products at higher cost of two Sicilian prescribing centers, i.e., Rheumatology and Dermatology centers, respectively from 2019 to 2020. To assess the prescribing appropriateness of these two centers, we evaluated the number of naïve patients treated with biosimilars, the amount of switching to the biosimilar products, and the motivations reported by clinicians, to justify the use of the biological products at higher cost.
Our analysis revealed that the number of biosimilar prescriptions at the time of the analysis was lower compared to the originators. Moreover, biosimilars have been prescribed but not for all the naïve patients, in contrast with the national and local directives. We also found that the switching from originators to biosimilars was negligible.
Finally, several motivations submitted by clinicians, related to prescription of drug with highest cost, were inappropriate and did not comply with Sicilian Regional Health System acts. The analysis revealed that, at the prescribing centers considered in this study, even if the number of biosimilar products at the time of the analysis was lower compared to the originators, biosimilars have been prescribed, but not for all the naïve patients, and the switching from originators to biosimilars was limited, confirming a high utilization of originators. Moreover, several reported motivations for prescription of high-cost biologics are considered inappropriate, according to the acts established by the Sicilian Regional Health System.

Impact statement
Biosimilars are interchangeable to biologics at high cost, specifically in terms of safety and efficacy. However, several efforts are still needed to spread the use of biosimilars, in order to contribute to the sustainability of the Health Care System.