Madrigal Pharmaceuticals extended its MASH strategy with another Arrowhead Pharmaceuticals deal, securing licensing rights for an siRNA candidate targeting a genetic driver tied to metabolic dysfunction-associated steatohepatitis. The package was structured as a potentially up to $1 billion biobucks licensing deal. Separately, Madrigal’s Rezdiffra continued to show commercial momentum, with reported first-quarter sales of $311 million that beat analyst estimates, reinforcing the company’s broader position in an area with mounting clinical and payer attention. Together, the transactions signal Madrigal’s push to build a layered MASH pipeline intended to complement its first approved therapy and reach more patient subtypes through mechanism-driven genetics.