Efficacy and safety of low dose sublingual nifedipine dripping pills (5 mg) in the acute treatment of moderate and severe hypertension: a randomized, double-blind, positive-drug parallel-controlled, multi-center clinical study

Abstract

Objective: To evaluate the efficacy and safety of low dose sublingual nifedipine dripping pills (5 mg) in treating moderate and severe hypertension in comparison with normal dose (10 mg) of sublingual nifedipine dripping pills. Methods: This study was designed as a randomized, double-blind, positive drug parallel controlled, multi-center, non-inferiority clinical trial. Patients with moderate and severe hypertension were enrolled by 14 clinical trial centers, randomly divided into the trial group (sublingual 5 mg nifedipine dripping pills) and the control group (sublingual 10 mg nifedipine dripping pills). The changes in blood pressure were monitored continuously within 2 hours after the initial administration, repeated the dose in 20 minutes interval after the initial administration for up to additional 3 doses (maximum 4 doses) if the antihypertensive efficacy was not satisfactory. The efficacy of antihypertensive therapy between the two groups was evaluated by repeated administration rates and blood pressure changes at 60 minutes post the initial administration, and the safety of treatment was evaluated by recording adverse event rate of the two groups. Results: The anti-hypertensive effective rates at 60 minutes after sublingual administration were 83.5% (202/242) and 86.7% (208/240) respectively between the trial group and control group (χ(2)=1.307, P=0.253) . On the aspect of antihypertensive effectiveness at 60 minutes after single dose of sublingual administration, the anti-hypertension effective rates of the trial group and the control group were 85.6% (154/180) and 87.2% (164/188) respectively (χ(2)=0.221, P=0.639). Prevalence of the repeated administration was also similar between the two groups (25.6%(62/242) in the trial group and 21.7% (52/240) in the control group, χ(2)=1.043, P=0.307). On the safety aspect, there was no adverse events/reactions in the trial group, but there were 15 cases of adverse events/reactions occurred in control group (6.25%, χ(2)=15.611, P<0.001). Conclusions: In the treatment of moderate to severe hypertension, the antihypertensive efficacy of low dose nifedipine dripping pills is similar to that of conventional dosage, and the safety profile of low dose nifedipine dripping pills is better than that of the conventional dose.