Novo Nordisk agreed a development and commercialization deal giving it global rights to zaltenibart, an Omeros MASP‑3 antibody, with up to $2.1 billion in payments tied to milestones. Novo will start pivotal testing in paroxysmal nocturnal hemoglobinuria (PNH) and explore kidney and other complement‑mediated disorders; Omeros retains royalty upside and near‑term cash. The transaction consolidates a growing pharma bet on complement biology as a commercial pathway for rare blood and renal diseases. MASP‑3 is a serine protease in the lectin complement pathway; inhibiting it offers a different mechanism than C5 blockade and may address both intravascular and extravascular hemolysis in PNH. Omeros’ earlier Phase 2 data showed improvements in hemoglobin and markers of hemolysis, which underpinned Novo’s decision to license the asset. The deal generated immediate market movement for Omeros and represents a strategic buy for Novo as it broadens beyond metabolic indications. Regulatory timing and Phase 3 design choices will determine whether zaltenibart can differentiate against established C5 inhibitors and newer complement modulators.