Boston-based cancer company Partner Therapeutics, Inc. (PTx) announced  that it has acquired the global rights to develop, manufacture, and commercialize Leukine (sargramostim) from Sanofi. Leukine is an immuno-stimulant that promotes the growth and activation of a broad range of white blood cells important in activating the body's immune response to fight infections. Leukine is used to treat or prevent severe and life-threatening infections and is the only immune modulator approved by the FDA for the treatment of acute myelogenous leukemia (AML) in older patients and for use in both allogeneic and autologous bone marrow transplantation.

In connection with the acquisition of Leukine, PTx will also acquire a dedicated manufacturing facility in Lynnwood, Washington. The facility is a state of the art biologics manufacturing plant that was certified for commercial production in 2012.  The Lynnwood facility will serve as the core manufacturing and supply chain center for PTx's operations. 

Leukine is the only FDA-approved recombinant human granulocyte-macrophage colony stimulating factor (GM-CSF). It has been demonstrated to promote growth and activation of monocytes, macrophages, neutrophils and dendritic cells.  It is currently indicated for the treatment of AML in older adults to reduce the incidence of severe and life-threatening infections resulting in death; use in the treatment of allogeneic bone marrow transplants to reduce the incidence of bacteremia and other culture positive infections and shorten the median duration of hospitalization; and to prolong the survival of patients who are experiencing bone marrow transplant failure or delay.

PTx will support the development of Leukine for new indications.  The product is being tested in a diverse set of clinical trials for its potential to improve survival and reduce adverse events in combination with leading immuno-oncology therapies. A 250 patient, randomized Phase II study in refractory melanoma in combination with ipilimumab demonstrated an improvement in survival (hazard ratio of 0.64) over ipilimumab alone¹.   Leukine is currently being tested in a Phase III trial in front-line melanoma in combination with ipilimumab and nivolumab, being conducted by the ECOG-ACRIN Cancer Research Group (Principal Investigator: F Stephen Hodi, MD, Director of the Center for Immuno-Oncology at Dana-Farber Cancer Institute) and sponsored by the National Cancer Institute (ClinicalTrials.gov Identifier: NCT02339571). 

Leukine is also in development for the treatment of Hematopoietic Syndrome of Acute Radiation Syndrome (H-ARS).  Data presented at the 2016 annual meeting of the American Society of Hematology, demonstrated Leukine's ability to increase survival in non-human primates exposed to myelosuppressive doses of radiation without supportive whole blood transfusions or individualized antibiotics².  A supplemental biologics licensing application (sBLA) was filed in September of 2017 with the FDA requesting approval of Leukine for the treatment of H-ARS.  In December, the application was granted Priority Review with a PDUFA date of March 29, 2018.