The FDA approved Yartemlea, Omeros’s complement‑system drug, for a severe and potentially fatal complication of hematopoietic stem cell transplants, marking the first regulator‑confirmed therapy for this condition. The approval provides a formal treatment pathway where none existed, with Omeros positioning the drug to address acute complement‑mediated pathology post‑transplant. Regulatory documents and company statements indicate the decision rests on clinical evidence demonstrating meaningful impact on clinical endpoints tied to the transplant complication. The approval will change inpatient and transplant center treatment algorithms and could prompt updates to transplant care protocols and payer coverage policies. Industry actors will watch uptake, labeling details, and post‑market requirements closely as transplant centers adapt clinical workflows.