Accurate, Reliable and Rapid CDC Assays

The importance of the complement system

The complement system plays a pivotal role in the innate immune system acting as an effector of adaptive immunity to remove common pathogens and unwanted cell types. The complement system can be activated through three major pathways: the classical, alternative and mannose-binding lectin. With relevance to therapeutic antibodies, the classical pathway is activated following binding of the C1 complex (C1q with C1r and C1s serine proteases) to the Fc region of a complement-fixing antibody that is bound to a target cell, initiating the complement cascade to kill cells through a process called complement-dependent cytotoxicity (CDC).

Determination of CDC activity of a biosimilars antibody should initially be conducted using a testing strategy composed of two orthogonal methods (a C1q binding assessment combined with a functional cell based CDC assay format) to determine the levels of similarity between the biosimilar and the reference innovator product. Where necessary, a range of investigatory assay formats can be applied to determine the significance of any differences on clinical efficacy and safety to demonstrate similarity.

Expertise in CDC Characterisation Strategies

Of the numerous effector function strategies that are employed to characterise biosimilars, a CDC assessment is probably the most simplistic as the number of required assay formats is reduced and those that are employed are less technically demanding than ADCC and ADCP. However, CDC activity of biosimimlar is still significantly influenced by certain product attributes that can vary between a biosimilar and the reference innovator product and it is critical that both C1q binding assays and functional cell based CDC assays demonstrate sufficient sensitive to these known product attributes and behave, together, as orthogonal methods.

Our experts are industry leaders in the understanding of the requirements for effector function characterisation having worked with a range of different biosimilar molecules that demonstrate a diverse range of similarity relative to the reference innovator product. With a wide portfolio of assays for different biosimilar molecules, we can help define a successful CDC characterisation strategy for your biosimilar and perform the required experiments.

Our CDC characterisation services include C1q binding assays, functional cell based methods using novel cell lines coupled with capabilities to conduct a diverse range of investigatory CDC assay formats for the following molecules:

Adalimumab (Humira); Bevacizumab (Avastin); Denosumab (Prolia);

Denosumab (Prolia); Etanercept (Enbrel); Golimumab (Simponi);

Infliximab (Remicade); Obinutuzumab (Gazyva); Pertuzumab (Perjeta);

Rituximab (Rituxan/MabThera); Tocilizumab (Actemra); Ipilimumab (Yervoy);

Trastuzumab (Herceptin) and Ustekinumab (Stelara)


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Custom CDC Development Services

With proprietary technology, cell line development capabilities and internal know-how we can develop industry-leading CDC assays across a wide range of different formats to support your molecule at all stages of development.

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