Pharmacoutilization of epoetins in naïve patients with hematological malignancies in an unselected Italian population under clinical practice setting: a comparative analysis between originator and biosimilars.

Aim: The purpose of this study was to assess the prescription of epoetins and consumption of health care resources (in terms of drug treatments) in naïve patients with hematological malignancies in a real-world setting; in particular, we compared the results between reference product and biosimilar products.

Methods: An observational retrospective study based on administrative and laboratory databases of three local health units was conducted. All adults diagnosed with hematological malignancies and who had received at least one epoetin (either reference product or biosimilars) prescription for the first time between 1 January 2010 and 30 April 2012 (enrollment period) were included. The date of the first prescription of epoetin within the enrollment period was defined as index date (ID). Patients were followed up for 4 weeks after ID (follow-up period) and were investigated for the 1-year period before the ID. The difference between the last hemoglobin (Hb) measurement after ID and the one prior to ID (ΔHb) was evaluated. The drug cost analysis was conducted from the perspective of the Italian National Health System.

Results: Overall, 69 patients were included in the study; 48 of them received reference epoetin product and 21 received biosimilars as first prescription. Among reference product users, the mean ± standard deviation (SD) age was 62.5±14.7 years; this cohort of patients was slightly significantly younger than the biosimilar users (71.8±11.8 years). The mean ± SD overall Hb level prior to treatment was lower among patients who started with biosimilar products (9.6±1.1 g/dL) compared to those who started with a reference product (10.1±2.1 g/dL). No significant differences in ΔHb were observed between biosimilar and originator groups during the followup period. The mean ± SD cost per patient was €667.98±573.93 and €340.85±235.73 for the reference product and biosimilar users, respectively (=0.065).

Conclusion: Our study showed that the use of biosimilar products might contribute to controlling health care costs (in terms of drug treatments) for patients with hematological malignancies being maintained by high-quality anemia therapy. Our findings also showed some discordances regarding the most appropriate therapeutic approach in daily clinical practice.