This week in therapeutics




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CD47; signal regulatory protein-a (SIRPA)

Cell culture and mouse studies suggest combining tumor-targeting mAbs with an engineered SIRPA variant could help treat cancer. Previous studies have shown that blocking the interaction between SIRPA and CD47 increased the immune response against tumor cells. In cell culture, treatment with an engineered SIRPA variant with high affinity for CD47 antagonized CD47 signaling and increased macrophage-mediated phagocytosis of tumor cells compared with treatment using wild-type SIRPA. In multiple mouse tumor xenograft models, engineered SIRPA increased the efficacy of tumor-targeting mAbs compared with vehicle. Next steps include making an IND submission and testing the engineered SIRPA as an adjunct to mAb therapies for cancer.
Radiation Control Technologies Inc. has the CD47 antagonist RCT1938 in preclinical development for various cancers.

SciBX 6(25); doi:10.1038/scibx.2013.619
Published online June 27, 2013

Patent pending; available for licensing

Weiskopf, K. et al. Science;
published online May 30, 2013;
Contact: K. Christopher Garcia, Stanford University School of Medicine, Stanford, Calif.