MK-0954E Phase III Long-Term Study in Participants With Hypertension (MK-0954E-356)

This study has two parts. In the first part, the efficacy and safety MK-0954E (losartan potassium 50 mg \[L50\] (+) hydrochlorothiazide 12.5 mg \[H12.5\] (+) amlodipine besylate 5mg \[A5\]) will be evaluated and compared to the efficacy and safety of MK-0954H (L50/H12.5) in Japanese participants. In the second part, the safety and tolerability of long-term use of open-label MK-0954E in participants with hypertension will be evaluated. The primary hypothesis is that MK-0954E is more effective in lowering mean trough sitting diastolic blood pressure (SiDBP) after 8 weeks of treatment compared to MK-954H (L50/H12.5 mg) in Japanese participants with essential hypertension who are not adequately controlled following a 8-week treatment with filter period study drug of MK-954H.