Horizon scanning and drug expenditure for rare diseases: three-year predictive model in Italy 2025–2027

Background and objective: In recent years, spending on orphan drugs in Italy has seen a significant rise. The analysis aims to estimate future spending for medicines for rare diseases (RDs) in Italy. Methods: A forecasting model was developed over a three-year time frame. New drugs were selected according to specific criteria, using Biomedtracker and clinical trial databases. For each therapeutic indication, comparators were identified to estimate the average cost per patient. Overall expenditure was projected by applying prevalence data to the eligible population, and considering expected drug uptake trends over the study period. Additionally, a deterministic sensitivity analysis was performed to assess the influence of price fluctuations on total pharmaceutical spending. Results: Overall, a total of 137 pipeline drugs for RDs were identified, covering 74 indications. The model estimated a total spending on RD treatments equal to €2.08 billion in 2024, corresponding to an average cost of €24,777 per patient. The projection indicates an increase by 1.9% in 2025, 4.0% in 2026, and 7.1% in 2027 compared to 2024. Focusing on orphan designation drugs (n = 115), the 2024 expenditure was estimated at €1.93 billion, with an average patient cost of €22,984. The introduction of new orphan drugs is expected to drive further increases in spending by 1.1% in 2025, 2.2% in 2026, and 3.7% in 2027. Conclusions: The results underscore the growing financial impact of orphan drugs on Italy's healthcare budget. This analysis offers a quantitative projection of the resources required to ensure continued access to innovative therapies for RDs.