Budget impact analysis of adalimumab biosimilar: the Italian context

Patients’ quality of life impairment together with a heavy burden to the National Health Service (NHS) and society are caused by chronic inflammatory diseases. Their treatment substantially improved with the advent of biological drugs (such as adalimumab), but these drugs are very expensive. At present, the patent protection of adalimumab (Humira®) has expired, and a biosimilar (Hyrimoz®) has been approved. Since the biosimilar price is expected to be lower as compared with the originator’s, the present Drug Budget Impact (DBI) analysis tries to evaluate whether and how much profitable the biosimilar availability will be for the Italian NHS, in terms of cost containment (savings). The time horizon in the analysis model is five years. The initial overall number of patients treated with adalimumab is estimated (based on the Italian population, the disease prevalence rates, the proportion of patients under treatment and adalimumab market share) and then kept constant in time. However, the model assumes that, year by year, patients in treatment with the originator will partly switch to the biosimilar (based on a prudent estimate of the uptake rate), while (due to a bolder estimate) a larger share of naïve patients will directly start with the biosimilar. Thanks to such assumptions, total number of patients treated with adalimumab (separately with the originator and with the biosimilar) is estimated, together with the respective total costs. According to the present analysis, the availability of the biosimilar would generate cumulated savings (in five years) as high as €260 millions for the Italian NHS.