FDA approved Takeda’s Mimrylo (rusfertide) for polycythemia vera, clearing the engineered peptide for a rare blood cancer with limited treatment options. The approval expands a commercial runway for Takeda as it prepares for broader label adoption in PV. Protagonist Therapeutics—Mimrylo’s developer—now has its second approval of 2026 following the FDA’s go-ahead for its partnership asset. Analysts expect the drug to become a meaningful revenue contributor depending on uptake across the PV population. The decision also reinforces the market demand for targeted therapies in myeloproliferative neoplasms, where weekly dosing and label breadth can materially affect prescribing patterns.