Novo Nordisk agreed to acquire global rights to Omeros’ zaltenibart (OMS‑906), an antibody targeting MASP‑3 in the complement cascade, in a deal structured for $340 million up front and up to $2.1 billion in milestones and royalties. Novo said it will initiate Phase 3 testing in paroxysmal nocturnal hemoglobinuria (PNH) and explore other complement‑mediated blood and kidney disorders where MASP‑3 inhibition could be differentiating. Omeros reported strong market reactions and characterized the transaction as validation of zaltenibart’s clinical potential, noting prior Phase 2 data in PNH. For readers: MASP‑3 is a complement pathway protease thought to enable alternative pathway activation; targeting it aims to reduce intra‑ and extravascular hemolysis in disorders such as PNH and certain nephropathies. Novo framed the buy as strategic diversification into rare disease complement biology.