Efficacy and tolerability of a switch to fixed-dose combination therapy with amlodipine besylate/benazepril hydrochloride after monotherapy with amlodipine besylate: Data from the African-American subpopulation of a practice-based, open-label study (the LOGIC study)

Abstract

Background: The LOGIC (LOtrel: Gauging Improved Control) study assessed the efficacy and tolerability of switching from amlodipine besylate monotherapy to fixed-dose combination therapy with amlodipine besylate/benazepril hydrochloride (HCI) in patients who were experiencing uncontrolled blood pressure (BP) or edema with monotherapy. Objective: This article reports the efficacy and tolerability of amlodipine besylate/benazepril HCI combination therapy in the predefined African-American population of the LOGIC study. Methods: This multicenter (1518 centers across the United States), practice-based, open-label, clinical trial enrolled patients with mild to moderate essential hypertension. Patients in group 1 had uncontrolled BP (sitting diastolic BP [DBP] ≥90 mm Hg and ≤110 mm Hg) during treatment with amlodipine besylate monotherapy 5 or 10 mg/d, and those in group 2 had controlled BP (sitting DBP ⩽90 mm Hg), but also had experienced edema during amlodipine besylate monotherapy. Participants were instructed to discontinue amlodipine besylate and were given amlodipine besylate/benazepril HCl 5/10 mg/d or 5/20 mg/d for 4 weeks. For group 1, the primary efficacy outcome was the change in mean sitting DBP (MSDBP) from baseline to week 4; a secondary efficacy outcome was the change in mean sitting systolic BP (MSSBP) from baseline to week 4. The primary efficacy outcome for group 2 was the percentage of patients whose edema improved with the switch to combination therapy. The secondary efficacy variables in group 2 were the changes in MSDBP and MSSBP from baseline to week 4. Patients in groups 1 and 2 were questioned about any adverse events that may have occurred since the previous visit. At both study visits, medications were reviewed, and the level of edema was assessed. Results: A total of 2055 African-American patients were enrolled in the study. At study end, African-American patients in group 1 (n = 1422 assessable patients) experienced significant reductions in MSSBP (13.9 mm Hg) and MSDBP (10.4 mm Hg) from those achieved during amlodipine besylate monotherapy (both P < 0.001). In group 2 (n = 266 assessable patients), 81% of African-American patients reported improvement in edema, and BP remained well controlled. Conclusions: In this study of an African-American subpopulation of patients with mild to moderate essential hypertension who had uncontrolled BP while receiving amlodipine besylate monotherapy, switching from amlodipine besylate monotherapy to fixed-dose amlodipine besylate/benazepril HCl combination therapy reduced BP to a greater extent than with amlodipine besylate alone, and reduced the incidence of edema in patients who were edematous but who had controlled BP. Fixed-dose combination therapy with amlodipine besylate/benazepril HCI has the potential to improve BP control, leading to improved clinical outcomes and enhanced treatment compliance.