Argenx and Zai Lab Enter Strategic Collaboration to Expand Reach of Autoimmune Therapy

Rare Daily Staff

Argenx, which is developing therapies for severe autoimmune diseases and cancer, said it entered into an exclusive license agreement with Zai Lab for the development and commercialization of efgartigimod in Greater China, including mainland China, Hong Kong, Taiwan, and Macau.

Efgartigimod is an experimental antibody fragment designed to reduce disease-causing immunoglobulin G (IgG) antibodies and block the IgG recycling process. Efgartigimod binds to the neonatal Fc receptor (FcRn), which is widely expressed throughout the body and plays a central role in rescuing IgG antibodies from degradation. Blocking FcRn reduces IgG antibody levels, representing a logical potential therapeutic approach for several autoimmune diseases known to be driven by disease-causing IgG antibodies, including myasthenia gravis, a chronic disease that causes muscle weakness; pemphigus vulgaris, a chronic disease characterized by severe blistering of the skin; immune thrombocytopenia, a chronic bruising and bleeding disease; and chronic inflammatory demyelinating polyneuropathy, a neurological disease leading to impaired motor function.

“Through this collaboration with Zai Lab, we are expanding our global footprint in one of the world’s fastest growing markets and reaching more people living with severe autoimmune diseases,” said Tim Van Hauwermeiren, CEO of Argenx. “By leveraging Zai Lab’s strong local expertise within Greater China and proven development capabilities, we aim to provide broad access to efgartigimod in these important markets as well as accelerate the number of autoimmune indications in clinical development.”

Under the terms of the agreement, Zai Lab obtains the exclusive right to develop and commercialize efgartigimod in Greater China. Zai Lab will recruit Chinese patients to Argenx’s global registrational trials for the development of efgartigimod. Additionally, this agreement is expected to allow Argenx to accelerate efgartigimod development by initiating multiple phase 2 proof-of-concept trials in new autoimmune indications.

Argenx will receive $175 million in collaboration payments, comprised of a $75 million upfront payment in the form of 568,182 newly issued Zai Lab shares calculated at a price of $132.00 per share, $75 million as a guaranteed non-creditable, non-refundable development cost-sharing payment, and an additional $25 million milestone payment upon approval of efgartigimod in the United States. Argenx is also eligible to receive tiered royalties (mid-teen to low 20s on a percentage basis) based on annual net sales of efgartigimod in Greater China.