This excerpt taken from the AMGN 10-K filed Mar 1, 2010.
Omecamtiv mecarbil (AMG 423)
Omecamtiv mecarbil is a small molecule activator of cardiac myosin. Omecamtiv mecarbil is being investigated to improve cardiac contractility in subjects with heart failure. We are developing this product in collaboration with Cytokinetics, Inc. (Cytokinetics).
In May 2009, Cytokinetics and Amgen Inc. announced that Amgen had exercised its option to obtain an exclusive license, worldwide (excluding Japan), to Cytokinetics cardiac contractility program, which includes omecamtiv mecarbil.