Partner Therapeutics (PTx) acquires the global rights to develop, manufacture, and commercialize sargramostim (Leukine, Sanofi). Sargramostim is the only Food and Drug Administration (FDA)-approved recombinant human granulocyte-macrophage colony stimulating factor. PTx will support the development of sargramostim for new indications; it is currently being tested in a phase III trial in frontline melanoma in combination with ipilimumab and nivolumab, as well as in the treatment of hematopoietic syndrome of acute radiation syndrome (H-ARS). A supplemental Biologics License Application was filed in September of 2017 with the FDA requesting approval of sargramostim for the treatment of H-ARS. In December, the application was granted Priority Review with a Prescription Drug User Fee Act date of March 29, 2018.