Amlodipine Prevents Morning Blood Pressure Surge Study
Status:
Completed
Trial end date:
2013-03-01
Target enrollment:
Participant gender:
Summary
1. Study name:Amlodipine Prevents Morning Blood Pressure Surge Study
2. Study drugs:amlodipine (Norvasc®) and nifedipine GITS (Adalat®)
3. Rationale: Several recent studies compared 24-h blood pressure lowering effect of these
2 dihydropyridine drugs, amlodipine and nifedipine GITS, but produced inconsistent
results. Therefore, a randomized controlled trial with a larger sample size is required
to compare these 2 dihydropyridines in the blood pressure control over 24 hours in
general and during early morning hours and at night in particular.
4. Objective: The primary objective of this study is to test the hypothesis that amlodipine
compared with nifedipine GITS has a stronger effect in preventing morning blood pressure
surge (4 am to 8 am) in mild to moderate hypertensive patients.The secondary objective
of the study is to compare the effects of amlodipine and nifedipine GITS in reducing
nighttime blood pressure (10 pm to 4 am) in patients with a decreased nocturnal blood
pressure fall.
5. Study design: The present study is designed as a randomized, actively controlled,
multi-centre parallel group trial (phase Ⅳ) with two equally sized treatment groups:
amlodipine and nifedipine GITS.
6. Study population: 500 hypertensive patients meet the inclusion/exclusion criteria.
7. Randomization and treatment: After stratification for centre, 500 eligible patients will
be randomized into 2 groups. 250 will receive amlodipine 5 mg per day, and 250 will
receive nifedipine GITS 30 mg per day. At 4 weeks of follow-up, the drug dosage per day
may increase to 10 mg of amlodipine and 60 mg of nifedipine GITS, if blood pressure
measured in doctor's office cannot be controlled to a level below 140/90 mm Hg. If there
were no compelling indication, no other antihypertensive drug is allowed during the
2-month trial.
8. Follow up: All patients should give written informed consent at entry into the present
study. In addition to 24-h ambulatory blood pressure monitoring, patients should also
undergo a questionnaire survey and clinical measurements including clinic blood
pressure. Patients will be followed up at the end of 4 weeks and 8 weeks after
randomization.
9. Sample size estimation: The number of required subject for the whole trial is 500.
10. Timeline: October 2009 to July 2013.
11. Organization: The Centre for Epidemiological Studies and Clinical Trials, Ruijin
Hospital, Shanghai, China.