Regadenoson.

Regadenoson is an adenosine A(2A) receptor agonist approved for use as a pharmacologic stress agent for radionuclide myocardial perfusion imaging in patients unable to undergo adequate exercise stress. Regadenoson causes a rapid increase in coronary blood flow, which is sustained for a short duration. In two phase III trials in patients with known or suspected coronary artery disease who were indicated for pharmacologic stress myocardial perfusion imaging, the agreement rate (in detecting reversible perfusion defects) between sequential adenosine-regadenoson scan images was noninferior to that between sequential adenosine-adenosine scan images. Regadenoson, compared with adenosine, was associated with a faster and greater peak increase in heart rate, but a slower return to baseline. The SBP and DBP decreased slightly with both agents; recovery to baseline levels was again faster with adenosine than with regadenoson. Regadenoson appeared to be generally well tolerated, with most adverse events beginning soon after administration and resolving within approximately 15 minutes. No unexpected treatment-emergent ECG changes occurred with regadenoson in the phase III trials.