A Phase III Randomized Controlled Trial Evaluating the Efficacy and Safety of Azilsartan Medoxomil and Amlodipine Combination Therapy in Patients With Mild-to-Moderate Essential Hypertension Inadequately Controlled on Monotherapy

PURPOSE: To assess the antihypertensive efficacy and safety of azilsartan medoxomil (AZM) and amlodipine (AML) combination therapy in patients with mild-to-moderate hypertension inadequately controlled by AZM or AML monotherapy. METHODS: In this multicenter, randomized, double-blind Phase III study (NCT05385770), patients with mild-to-moderate hypertension inadequately controlled with AZM 40/80 mg or AML 5/10 mg were randomized (1:1:1) to receive low-dose or high-dose AZM/AML combination therapy or continued monotherapy as control. Eligible patients completed a 4-week active run-in period before randomization. The primary endpoint was change from baseline in mean sitting systolic blood pressure (SBP) after 8 weeks of treatment. FINDINGS: A total of 890 patients were randomized. AZM/AML combination therapy resulted in significantly greater reductions in mean sitting SBP compared with AZM or AML monotherapy across all dose groups. Least-squares mean reductions in mean sitting SBP at week 8 ranged from 5.2 to 9.0 mm Hg across all monotherapy nonresponder groups, with all comparisons showing statistical significance (P < 0.05). Reductions in mean sitting diastolic blood pressure also favored combination therapy. Safety profiles were comparable across all treatment arms, with most adverse events mild or moderate in severity. No additional safety concerns were identified compared with monotherapy. IMPLICATIONS: AZM/AML combination therapy was more effective than monotherapy in patients with mild-to-moderate hypertension inadequately controlled with either agent alone, even at maximum doses. Both low-dose and high-dose combinations were well tolerated. AZM/AML combination therapy may offer enhanced BP-lowering efficacy compared with other angiotensin II receptor blocker-based regimens.