Ionis' investigational antisense medicine for the treatment of transthyretin amyloidosis (ATTR), following expiration of the waiting period under the Hart-Scott-Rodino Antitrust Improvements Act of 1976 (HSR Act).

Eplontersen, formerly known as IONIS-TTR-L_Rx, is designed to reduce the production of transthyretin, or TTR protein, to treat ATTR, a systemic, progressive and fatal disease. It uses Ionis' advanced LIgand-Conjugated Antisense (LICA) technology.

As previously announced, the companies will jointly develop and commercialize eplontersen in the U.S. AstraZeneca has an exclusive license for eplontersen outside the U.S., except certain countries in Latin America. Under the terms of the agreement, Ionis will receive a $200 million upfront payment, up to $485 million in development and approval milestones, and up to $2.9 billion in sales-related milestone payments. The collaboration includes territory-specific development, commercial and medical affairs cost-sharing provisions. Ionis is also eligible to earn royalties in the range of low double-digit to mid-20s percentage depending on region. Additional details about the agreement can be found in Ionis' Form 8-K filed with the Securities and Exchange Commission on Dec. 7, 2021.