Efficacy of morning and evening dosing of amlodipine/valsartan combination in hypertensive patients uncontrolled by 5 mg of amlodipine.

Objectives: This study compared the effects of morning and evening dosing of amlodipine/valsartan combination on 24-h blood pressure (BP) in patients uncontrolled by amlodipine (5 mg).

Methods: This was a multicenter study that used a prospective, randomized, open-label, blinded endpoint design. Patients with essential hypertension, who's ambulatory BP was uncontrolled after 4 weeks on amlodipine (5 mg) were randomized to receive amlodipine/valsartan (5/160 mg) for 8 weeks in the morning or evening (n=231, 232, respectively), with optional uptitration up to 10/160 mg after 4 weeks if the office BP was uncontrolled. A 30-h ambulatory BP measurement was taken at randomization and at the end of the study.

Results: Morning and evening dosing with amlodipine/valsartan had equivalent effects on systolic BP (mean 24 h, daytime, night-time, and 24-30 h) and diastolic BP (mean 24 h, daytime, night-time, and 24-30 h). There was a small difference in the night-time diastolic BP (-4.92 vs.-6.20 mmHg; P=0.02) and a slight but nonsignificant trend for higher BP reduction during daytime for morning intake and during night-time for evening intake. BP control rates based on 24-h ambulatory BP measurement values (<120/80 mmHg) were similar between morning and evening dosing (47 vs. 45%).

Conclusion: These results indicate that, in patients with BP uncontrolled by amlodipine (5 mg), morning and evening treatment with amlodipine/valsartan combination have similar effects on circadian BP, especially when 24-h mean values are considered.