Madrigal Pharmaceuticals struck an exclusive agreement to add six preclinical siRNA programs from Ribo Life Science in a deal that could pay out up to $4.4 billion. The transaction includes a roughly $60 million upfront payment and royalties, and it is explicitly aimed at expanding Madrigal’s metabolic dysfunction‑associated steatohepatitis (MASH) franchise around Rezdiffra. The company frames the deal as a route to combine gene‑silencing approaches with its thyroid hormone receptor‑beta agonist to address multiple drivers of fatty‑liver disease. Madrigal has been actively building a multi‑asset MASH strategy through recent acquisitions and licenses; executives say targeted siRNAs complement its existing small molecule and biologic programs and could help sustain Rezdiffra‑led commercial momentum as competition intensifies.