OBJECTIVETo evaluate the effectiveness and safety of L-amlodipine besylate for blood pressure control in patients with mild to moderate essential hypertension.

METHODA total of 1051 mild to moderate essential hypertensives were recruited from 22 centers and randomized into three groups and were given low-dose L-amlodipine besylate (2.5 mg/d), high-dose L-amlodipine besylate (5.0 mg/d), and amlodipine maleate (5.0 mg/d) on the principle of open-label and parallel control. The study drugs were administered for 8 weeks.

RESULTSAfter 8 weeks treatments, the response rate of the three groups were 72.4%, 85.6%, and 76.2%, respectively. The rate difference between high-dose L-amlodipine besylate group and the other two groups were statistically significant (P < 0.01), while the rate difference between low-dose L-amlodipine besylate group and amlodipine maleate group was similar (P = 0.28). The event rates of the three groups were similar (4.3%, 4.6%, and 5.1%, respectively, P = 0.84).

CONCLUSIONHigh-dose L-amlodipine besylate is superior to the other 2 groups on blood pressure control. The efficacy profiles of amlodipine maleate and low-dose L-amlodipine besylate are equivalent. Safety profiles of these three groups are comparable.