Table III.
Clinical Trials to Evaluate Dual Calcium Channel Blocker Therapy in Hypertension
| Reference | Disease and Number of Subjects | Study Design | Monotherapy (Mean Dosage) | Dosage of Dual Therapy | Results of Dual Therapy |
| Comerio et al. 15 | Hypertension n=13 | R/D‐B | Lacidipine 4 mg/d; verapamil 240 mg/d | Lacidipine 4 mg/d with verapamil 240 mg/d | Combined lacidipine and verapamil reduced BP from 160±11/101±7 to 140±11/92±5 |
| Kiowski et al. 20 | Hypertension n=8 | O‐L, cross‐over | Amlodipine 44.5 µg/min/100 mL of forearm tissue | Amlodipine 44.5 µg/min/100 mL 2.5 h of forearm tissue with verapamil 40 µg/min/100 mL of forearm tissue | ↑ forearm blood flow (2.9±1.7 to a maximum of 23.6±7.6 mL with amlodipine); further increase to 34.4±9.8 mL/min/100 mL with verapamil |
| Andreyev et al. 12 | Hypertension and stable effort angina n=16 | O‐L, cross‐over | Diltiazem 240 mg/d; nitrendipine 20 mg/d | Diltiazem 120 mg/d with nitrendipine 20 mg/d | Better BP control compared with diltiazem monotherapy but not nitrendipine monotherapy; better ischemic control with dual therapy |
| Nalbantgil et al. 21 | Hypertension n=40 | R/P‐C/D‐B, cross‐over | Verapamil 240 mg/d and nitrendipine 20 mg/d | Verapamil 120 mg/d with nitrendipine 10 mg/d | Improved BP control and fewer adverse effects with dual therapy |
| Kaesemeyer et al. 17 | Mild hypertension n=23 | Retrospective analysis | Verapamil 120–360 mg/d with nifedipine 30–90 mg/d | BP controlled in 100% (23/23) and leg edema in 30% (7/23) | |
| Kaesemeyer et al. 17 | Moderate to severe hypertension n=27 | Retrospective analysis | Verapamil 120–480 mg/d with nifedipine 180 mg/d or verapamil 480 mg/d with nifedipine 30–180 mg/d | BP controlled in 89% (24/27) and leg edema in 26% (7/27) | |
| Saseen et al. 18 | Hypertension n=16 | R/D‐B, three‐period crossover | Nifedipine‐SR 30 mg/d | Nifedipine‐SR 30 mg/d with either diltiazem‐SR 180 mg/d or verapamil‐SR 180 mg/d; cross‐over to diltiazem or verapamil | Both combinations ↓ systolic and diastolic BP more than nifedipine alone; verapamil and diltiazem ↑ nifedipine plasma concentrations by 49% and 21%, respectively; 50% of subjects with constipation in the nifedipine and verapamil group |
| R=randomized; D‐B=double‐blind; O‐L=open‐label; P‐C=placebo‐controlled; BP=blood pressure; SR=sustained release Adapted with permission from Ann Pharmacother. 1996;30:802–810. 16 | |||||