OBJECTIVE: To evaluate the efficacy and safety of olmesartan medoxomil (20 mg and 40 mg) in Filipino subjects with mild to moderate essential hypertension. METHODS: Sixty-seven (n = 24 male; n= 43 female) Filipino outpatients (mean age Sl.lill.5 years) with mild to moderate hypertension entered this 8-week, open-label, dose titration, treat-to-target study; n = 62 patients completed. All subjects received olmesartan 20 mg for four weeks, at which time a dose titration assessment occurred. Subjects were either maintained on 20 mg or up-titrated to 40 mg for the final four weeks. Intent-to-treat analysis were performed using last observation carried forward (LOCF) methodology on the percentage of subjects achieving blood pressure (BP) target (responders were pre-specified using the JNC VII guidelines) at Weeks 4 and 8 (primary endpoint). Safety was assessed by incidence of adverse events (AEs) and subject discontinuations. RESULTS: A large proportion of subjects achieved BP target at Week 8/LOCF (59 percent, n = 39); moreover, 48 percent (n-31) responded at Week 4. A further 11, of the 33 subjects not at target at Week 4, went on to achieve BP target by Week 8/LOCF. Overall, mean BP at baseline was 155.4/95.8 mmHg, which was reduced to 127.2/80.3 following eight weeks of treatment. Seven subjects reported 12 treatment-related AEs; the most common was headache (n-3). There were no serious AEs reported during the study and only one subject had severe AEs (headache, insomnia and facial flushing); this subject was the only subject who discontinued due to treatment-related AEs. CONCLUSION: Olmesartan medoxomil was found to be an effective, safe and well-tolerated antihypertensive agent in this Filipino population, with 59% of subjects reaching their BP target by the end of the study. These data are supportive of findings in other populations, and will provide valuable information for Filipino clinicians for management of hypertension.