I think jdat was referring to belatacept, an investigational drug developed by Bristol-Myers Squibb. They are already in phase III after a successful phase II. It is quite interesting and could provide a viable alternative to conventional immunosuppressive drugs in the future if the results of phase II are confirmed. I mentioned it to my nephrologist and he said he was a bit skeptical because the clinical trials were financed by the drug company and might have been biased in their favor. But even he admitted that the results so far were very encouraging.
More info at:
http://www.medscape.com/viewarticle/505462