A Double-Blind Comparison of Moxonidine and Atenolol in the Management of Patients with Mild-to-Moderate Hypertension

The safety and efficacy of moxonidine, a new imidazoline receptor modulator, were compared with those of atenolol in 63 patients with mild-to-moderate essential hypertension in a multicenter, randomized, double-blind, parallel-group trial. The study consisted of a 4-week singleblind placebo run-in phase, an 8-week double-blind active therapy period, and a 2-week single-blind washout phase on placebo. On an intention-to-treat basis (n = 63), average sitting blood pressure decreased from 166 ± 10/100 ± 5 mm Hg to 149 ± 21/90 ± 9 mm Hg in the moxonidine group and from 169 ± 11/101 ± 6 mm Hg to 149 ± 21/87 ± 8 mm Hg in the atenolol group at Week 12. Responder rates (diastolic blood pressure of ≤ 90 mm Hg) were 65.5% and 70.6% respectively. In the per-protocol analysis (n = 53), corresponding values were 167 ± 8/101 ± 3 mm Hg to 148 ± 22/89 ± 10 mm Hg in the moxonidine group and 169 ± 12.102 ± 4 mm Hg to 145 ± 17/87 ± 8 mm Hg in the atenolol group. Responder rates in these patients were 68.0% for moxonidine and 71.4% for atenolol. No significant between-group differences could be found for any of these variables. Treatment emergency signs or symptoms were reported by 15 patients6 events occurred in 6 patients during treatment with moxonidine, and 16 events occurred in 9 patients during treatment with atenolo. Two atenolol patients were with-drawn prematurely from the study because of adverse events, i.e., cold extremities and nightmares, and calf pain. The findings suggest that moxonidine is as effective as atenolol in the management of essential hypertension at the doses administered. It appears to be as well tolerated as atenolol. but larger studies are required to confirm the lower incidence of side effects with moxonidine.