King's image problem

When King Pharmaceuticals Inc. began Phase III testing of its CorVue binodenoson as a pharmacological stress agent for radionuclide myocardial perfusion imaging (MPI) in December 2003, the compound was neck-and-neck with rival Lexiscan regadenoson from CV Therapeutics Inc., which entered Phase III only two months prior.

Both had potential to be first-in-class adenosine A2A receptor agonists. Six years later, Lexiscan has been on the market for over a year, while King will likely have to run another trial. The difference lies in the details: CVT accounted for the variability of the images in its trials, while King did not...