Antibody Research

Preclinical and clinical pharmacokinetic (PK) studies require highly specific and high affinity immunoassays to evaluate the safety and efficacy of therapeutic monoclonal antibodies (MAbs). In addition to the requirement that immunoassays specifically detect therapeutic MAbs without interference from host serum proteins, it is increasingly critical to develop reagents that allow differentiation between Free (Unbound) and Total (Bound + Unbound) drug. These reagents help to more fully characterize in vivo drug:target interaction and illustrate the full pharmacologic effect of therapeutic MAbs.

We describe here efforts to evaluate a panel of antibodies specific to ETI204 and the identification of antibody pairs to allow differential quantitation of either Free or Total ETI204 in the presence of PA.


MAbs and ELISAs have been developed that are suitable for the measurement of Free and Total Obiltoxaximab from Human or Cynomolgus serum in the presence of Anthrax Protective Antigen.

Download this poster

We invite you to download our poster that details this research study, including our antibody discovery strategy as well as the Spike protein reagents, screening assay formats, and more that we utilized.

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Joshua K. Lowitz1, John P. Nichols1, Sarah E. Carpenter2, Edward F. O’Connor3 and John S. Kenney1

1Antibody Solutions, 2Elusys Therapeutics, 3Alexion Pharmaceuticals