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Efgartigimod Case Study: A Human IgG1 Antibody Fc Fragment
Efgartigimod (ARGX-113) was engineered based on the seminal research of Prof. E. Sally Ward, Ph.D., while at UT Southwestern.
Prof. Ward is an antiobody pioneer. Her research identified the role of FcRn as a key receptor involved in the long persistence and tissue penetration of IgG antibodies in the human body.
Our team, in close collaboration with Prof. Ward, designed Efgartigimod to modulate normal FcRn function in a unique fashion. It has shown encouraging results during proof-of-concept studies in multiple potential indications, which are known to be IgG-mediated: myasthenia gravis (MG) and immune thrombocytopenia (ITP).
Efgartigimod is being investigated in a range of autoimmune indications where IgG antibodies are a mediator of disease.
Proposed Mechanism of Action
Efgartigimod is a human IgG1 antibody Fc fragment that has been engineered for increased affinity to FcRn compared to endogenous IgG, and is uniquely composed of the only part of the IgG antibody that normally binds FcRn. Efgartigimod selectively reduces IgG by blocking FcRn-mediated IgG recycling.
- Efgartigimod and IgG are internalized into the cell
- Efgartigimod outcompetes endogenous IgG antibodies and pathogenic IgG autoantibodies for binding to FcRn, due to increased affinity to FcRn
- When bound to FcRn, efgartigimod and IgG escape lysosomal degradation
- Remaining unbound IgG and efgartigimod are degraded in the lysosome
- Efgartigimod and fewer IgGs are recycled back into circulation
Publications
Further explore efgartigimod and the science behind it.
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For more information on partnering opportunities, please contact IIP@argenx.com.
Explore More
At argenx, every piece of the innovation story connects. See where it leads next.
Antibody Engineering
See how our platform technologies help optimize antibodies and amplify possibilities in immunology.
Co-Creation in Action
See what happens when our team takes promising leaps alongside leading scientists, physicians, and researchers.
Publications
Peer-reviewed publications that reflect our range of immunology innovation.
