Comparison in Japan T80/A5 (Telmisartan 80 mg and Amlodipine 5 mg) and T40/A5 (Telmisartan 40 mg and Amlodipine 5 mg)

An Eight-week Randomised Double-blind Study to Compare the Efficacy and Safety of Telmisartan 80mg Plus Amlodipine 5 mg Fixed-dose Combination vs. Telmisartan 40 mg Plus Amlodipine 5 mg Fixed-dose Combination in Patients With Hypertension

Blood pressure in hypertensive patients is rarely controlled to an optimal level by one drug alone, often a combination of two or more drugs is essential to achieve a sufficient antihypertensive effect. Therefore in Japanese Society of Hypertension (JSH) 2009 combination therapy is recommended. In JSH 2009 it is advised to start the combination therapy at a low dose, and to increase the dosage when the antihypertensive effect is not sufficient. In the Japanese long-term safety study, 259 patients received the T40/A5 mg fixed-dose combination (FDC), and after 6 weeks treatment 48 patients of them could not control their blood pressure (DBP =90) (U09-2494-01). For those patients who cannot control their blood pressure with T40/A5 mg FDC, a switch to a higher dose such as T80/A5 mg is recommended.

In the overseas 4x4 factorial design trial, a clinically meaningful difference of the blood pressure lowering effect between T80/A5 mg free combination and T40/A5 mg free combination was shown (U07-3503-02). But the sponsor has no data that verifies this difference in Japanese patients.

Thus, this clinical trial is being conducted to investigate the antihypertensive effect and safety of high dose T80/A5 mg FDC compared with low dose T40/A5 mg FDC in Japanese patients with essential hypertension. In this trial, a multi-centre, randomised, double-blind, double-dummy, active-controlled, parallel group comparison method is employed.

Inclusion criteria:

1. Essential hypertensive patients

   • If already taking antihypertensive drugs, mean seated diastolic blood pressure (DBP) must be >=90 and >=114 mmHg
   • If not taking any antihypertensive drugs, mean seated DBP must be >=95 and >=114 mmHg

2. Able to stop all current antihypertensive drugs without risk to the patient based on the investigators opinion.

Exclusion criteria:

1. Patients taking 3 or more antihypertensive drugs at signing the informed consent form
2. Patients with known or suspected secondary hypertension
3. Patients with clinically relevant cardiac arrhythmia
4. Congestive heart failure with New York Heart Association (NYHA) functional class III-IV
5. Patients with recent cardiovascular events
6. Patients with a history of stroke or transient ischaemic attack within last 6 months before signing the informed consent form
7. Patients with a history of sudden deterioration of renal function with angiotensin II receptor blockers (ARBs) or angiotensin converting enzyme (ACE) inhibitors; or patients with post-renal transplant or post-nephrectomy
8. Patients who have previously experienced characteristic symptoms of angioedema (such as facial, tongue, pharyngeal, or laryngeal swelling with dyspnea) during treatment with ARBs or ACE inhibitors
9. Patients with known hypersensitivity to any component of the investigational product, or a known hypersensitivity to dihydropyridine-derived drugs
10. Patients with hepatic and/or renal dysfunction
11. Pre-menopausal women who are nursing or pregnant