OBJECTIVE Calcium antagonists, angiotensin-converting enzyme (ACE) inhibitors and other drug classes either alone or in combination have been recommended for the treatment of hypertension. Nifedipine gastrointestinal therapeutic system (GITS) 20 mg is a new low-dose formulation with an improved tolerability. The aim of the present study was to compare the effects of nifedipine GITS 20 mg and enalapril 20 mg on blood pressure and circulating adhesion molecules in hypertensive patients. METHODS This randomized, double-blind, multicentre trial compared the blood pressure lowering effects of a 12-week treatment of nifedipine GITS 20 mg vs enalapril 20 mg in 264 patients with mild-to-moderate hypertension. RESULTS Nifedipine GITS 20 mg induced a reduction of clinic blood pressure, which was similar to that observed with enalapril 20 mg. Nifedipine GITS and enalapril lowered mean sitting diastolic blood pressure by 11.8 and 12.4 mmHg, respectively, while systolic blood pressure was reduced by 15.3 and 16.3 mmHg, respectively. Ambulatory blood pressure monitoring-derived blood pressure data showed similar results in both groups without any statistically significant differences between treatments. Both enalapril and nifedipine tended to reduce ICAM-1 and E-selectin, while only nifedipine reduced von Willebrand factor. Both treatments were well tolerated. CONCLUSIONS Our findings demonstrate a similar antihypertensive effectiveness of a low dose (20 mg) of nifedipine GITS in comparison with a standard dose of enalapril (20 mg). Given its clinical efficacy and good tolerability, low-dose nifedipine GITS may be considered a valuable treatment option for hypertensive patients.