Antihypertensive effect of levcromakalim in patients with essential hypertension. Study by 24-h ambulatory blood pressure monitoring.

Levcromakalim (BRL 38227, CAS 94535-50-9) is a new antihypertensive drug with vasodilator activity due to activation of potassium channels in vascular smooth muscle. In this study, we treated 14 patients with essential hypertension on an out-patient basis to investigate the antihypertensive effect of levcromakalim by 24-h blood pressure monitoring for a 12-weeks treatment period. Levcromakalim significantly lowered blood pressure for 24 h without affecting standard deviation, range of variation and pulse rate. When 24-h monitoring period was divided into daytime (6:00-22:00) and nighttime (22:30-5:30), there were no statistically significant differences in magnitude of fall in blood pressure at night between baseline and end of treatment values. Four patients (28.5%) reported 6 adverse events, including headache, facial hot flushes, oedema and floating feeling. All symptoms were mild or moderate. These data show that levcromakalim controls ambulatory blood pressure both in the daytime and nighttime without changing the circadian rhythm of blood pressure, and suggest that levcromakalim will be an efficacious and safe antihypertensive drug.