Biopharmaceutical immuno-oncology company Stem Cell Therapeutics (SCT) has entered an agreement to exclusively license worldwide rights to a panel of fully human monoclonal antibodies targeting the SIRPa protein (CD172a). This technology was developed by scientists at the University Health Network, the University of Toronto, through the Toronto Recombinant Antibody Centre, and the Hospital for Sick Children, also in Toronto.
SIRPa is the ligand of CD47, a molecule upregulated on many hematological and solid tumors. SCT is currently developing a CD47 antagonist using a modified version of the native SIRPa protein fused to an immunoglobulin Fc region. The firm says that this SIRPaFc fusion protein has shown antileukemic activity both in vitro and in human xenograft models, and the program has reportedly entered the IND-enabling phase of drug development.
"Targeting the CD47/SIRPa pathway can eliminate both bulk cancer cells and cancer stem cells, and engages both the innate and the adaptive arms of the immune system," said Bob Uger, Ph.D., SCT's CSO. "Antibody blockade of SIRPa is a promising approach to activate the antitumor activity of macrophages against both liquid and solid tumors, and has the potential as both a monotherapy and combination therapy with other anticancer antibodies."