Clevidipine is a short-acting dihydropyridine calcium channel antagonist (IC50= 7.1 nM, V(H) = -40 mV ) under development for treatment of perioperative hypertension. IC50 Value: 7.1 nM at V(H) = -40 mV [1] Target: calcium channel in vitro: Both clevidipine and nitroglycerin completely reversed U46619-induced contraction (clevidipine (50% effective concentration [EC50] = 3.88 +/- 0.84 x 10(-6) mol/L, nitroglycerin EC50 = 4.84 +/- 2.76 x 10(-8) mol/L) [2]. A decrease in temperature increased the half-life of clevidipine in blood, whereas dilution of the blood did not affect the in vitro half-life of clevidipine. The albumin concentration affected the hydrolysis rate of clevidipine in RBC suspended with saline [3]. in vivo: Clevidipine is a high-clearance drug with a relatively small volume of distribution, resulting in an extremely short half-life in all species studied. The median initial half-life of the individual value (Bayesian estimates) is 12, 20, and 22 s in the rabbit, rat, and dog, respectively [4]. The extremely high clearance value and the small volume of distribution resulted in short half-lives of clevidipine, 2.2 and 16.8 min, respectively. The blood concentration and dose rate producing half the maximal effect (i.e. EC50 and ED50) were approximately 25 nM and 1.5 microg/kg/min, respectively [5]. Clinical trial: CARVE: Clevidipine for Vasoreactivity Evaluation of the Pulmonary Arterial Bed. Phase 4