OBJECTIVES: Rituximab is a chimeric monoclonal antibody targeted against CD20 which is a surface antigen present on B cells. In last 20 years Rituximab becomes a standard of care for treatment of several rare diseases like Chronic lymphocytic leukemia, Folicular limphoma and Diffuse large B-cell lymphoma. It is expected that the entry of biosimilars on the market will lead to a reduction in the cost of drug therapy.

METHODS: Review of the marketing authorization (MA) status of Rituximab and its biosimilars in the EU and pricing registry in the selected countries. Analysis of the registered prices in Bulgaria, France, Greece and Slovakia and National Health Insurance Fund (NHIF) cost in Bulgaria have been performed.

RESULTS: The first biosimilar of Rituximab has registered price between 9-10 months (Bulgaria, France and Greece), and 14 months (Slovakia) after MA in 2017. The biosimilar prices per mg are 34% on average lower than the original product. In Bulgaria and Slovakia the launch of the next Rituximab biosimilar leads to further price reduction. Biosimilars launch in oncohematology in Bulgaria reduced with 35% NHIF costs: from 6 090 127 Euro in 2017 to 3 940 697 Euro in 2020. In 2020, 29% of the NHIF costs of intravenous Rituximab are for biosimilars which are almost tripled compared to 2018.

CONCLUSIONS: The results of the review show that biosimilars launch reducing the cost of therapy. The decrease in the registered prices of Rituximab is mainly due to regulatory requirements. Further reductions can be expected following the relevant tender procedures or specific agreements, as Rituximab in oncohematology is for hospital use, but due to confidentiality this information is difficult to be assessed. However, further analysis could be made as to whether the savings on drug therapy lead to an increase in patients' access to innovative drug therapies.