Biological function comparison between a Proposed Biosimilar and Originator Rituximab

HÉCTOR CUELLO; SEGATORI VALERIA INÉS; DANIEL E GOMEZ; ALONSO DANIEL F; PESCE A; GABRI MARIANO R

Rosario

Congreso; Congreso anual de la Sociedad Argentina de Investigaciones Bioquímicas, SAIB; 2014

SAIB

Similar biotherapeutic products (SBPs) are reaching the market, earning acceptance and becoming a reality. A wide range of SBPs are under development or are already licensed in many countries. In this scenario, functional comparability assays are key elements in demonstrating biosimilarity, particularly when they assess the actual mechanisms of action of the molecule. In this work, we report a comparison of the binding capacity and the in vitro ADCC induction of a SBP and Mabthera©. By quantitative FACS we evaluated the binding of the SBP to CD20-positive cells. No differences in binding capacity were observed between the products.It has been described that FcγRIIIA-158 polymorphisms phenylalanine/valine (F/V) or valine/valine (V/V) are important for predicting rituximab ADCC response. We tested thesepolymorphismsin healthy donors by PCR and sequencing, finding that 4 out of 12 were positive. The induction of ADCC was evaluated with a lactate dehydrogenase release-based method using peripheral blood mononuclear cells of a positive donorin an Absdose-response manner. We observed equivalent efficacy between SBP and Mabthera©. Additionally, our results also confirmed that donors with F/F polymorphism induced a lower ADCC response as it is reported. In summary, Similar Binding and ADCC activity was shown for both Mabthera and the evaluated biosimilars.