The research being produced by the Irv Weissman lab is showing some outstanding promise in murine models. If this work is also being conducted outside of academia, I don't think the players have as yet shown their hand. SGEN's ADC collaboration pipeline is loaded with wild cards, however, and the "undisclosed ADC's" listed w/ Bayer, Pfizer, Astellas, and GSK all may have CD-47/ TSP-1/ SIRP inhibitor/ activator potential. Stanford's claim to initiate human trials by mid-2014 may tease some commercial research into the spotlight. Best to keep an eye out.
In fact, I think the concept of CD-47 inhibition is extremely under-addressed. If you do a search at clinicltrialsdotgov for CD-47, you'll find one trial being conducted by Genentech. They've been working on CD-47 as a prognostic biomarker in advanced Multiple Myeloma in a collaboration w/ the Univ of South Carolina since 2011.
Forces me to ponder the commercial potential. Maybe it's a cheap & natural process.
If BP can't synthesize it, patent it, and monetize it...they're generally not interested.