Highly purified charge variants of a proposed biosimilar to Omalizumab: impact on in vitro potency and stability under thermal stress.

Biosimilars are highly complex and similar biological drugs are developed with different manufacturing processes which are not similar to originator manufacturing process. Due to this, biosimilar products inherently have quality differences in comparison to innovator molecule which may be related to size, charge and glycosylation. Despite these differences they are supposed to demonstrate similar behaviour in safety and efficacy profile to the reference product and these differences should not be clinically meaningful. Charge variants are one of the critical quality attributes and sources of heterogeneity. In this study, highly purified charge variants cluster (acidic, main peak and basic) of biosimilar product of Xolair were assessed for their impact on in vitro potency and stability at different thermal stress conditions (2-8 °C and - 20 °C). The study data indicating purified charge variants (> 90%) have no impact on in vitro potency and are stable at different thermal stress conditions up to a week.