Argenx grants autoimmune drug's Greater China rights to Zai Lab for $75M

Argenx SE is granting Zai Lab Ltd. exclusive rights to its experimental autoimmune disease therapy efgartigimod in Greater China.

Under the licensing deal, argenx will receive an up-front payment of $75 million in the form of 568,182 newly issued Zai Lab shares calculated at a price of $132 each. Argenx will also receive $75 million as a guaranteed noncreditable, nonrefundable development cost-sharing payment, as well as an additional $25 million if efgartigimod wins U.S. approval. In addition, argenx is eligible to receive tiered royalties based on annual net sales of the drug in Greater China.

In return, Shanghai-based Zai Lab will have exclusive rights to develop and market efgartigimod in the territory, which includes mainland China, Hong Kong, Taiwan and Macao. The company will also recruit Chinese patients to argenx's global registrational trials for the development of efgartigimod.

Argenx said it will be initiating multiple mid-stage proof-of-concept studies of the drug for autoimmune indications to speed up the development of the efgartigimod.

Efgartigimod is under review by the U.S. Food and Drug Administration for treating generalized myasthenia gravis, a rare and chronic autoimmune neuromuscular condition characterized by varying muscle weakness. In a late-stage study dubbed Adapt, the drug was shown to improve symptoms of the disease.

In 2018, the company reported that efgartigimod delivered clinically meaningful platelet count improvements to patients in a mid-stage study in the treatment of a blood disorder known as primary immune thrombocytopenia.