Acute and chronic effects of felodipine extended release and amlodipine in patients with exertional angina: A double-masked, clinical comparison

In this randomized, double-masked, parallel-group study of patients with stable exertional angina, the acute (4 hours after administration of the first dose) and chronic (23 hours after administration of the last dose) therapeutic effects of a 28-day treatment regimen with either felodipine extended release (ER) or amlodipine were compared. Both drugs were given orally once daily at a dosage of 10 mg, There were 30 patients enrolled and 29 completed the study; 1 patient treated with amlodipine withdrew due to severe ankle edema, Analysis within treatment groups showed that the acute effect of felodipine ER produced a statistically significant improvement (compared with baseline) in time to test termination, time to onset of ischemia, rate-pressure product at onset of angina, and maximal ST-segment depression, In contrast, in the amlodipine group, only maximal ST-segment depression improved significantly with acute treatment. No statistically significant difference between the felodipine ER and amlodipine groups was seen with respect to acute effect, However, with respect to chronic effect, a significant difference was demonstrated in time to test termination and time to onset of ischemia, both of which were significantly longer after treatment with felodipine ER compared with amlodipine.