The efficacy of telmisartan and amlodipine tablets for treatment of hypertension was studied in one placebo-controlled and two active-controlled trials. 

An 8-week multicenter, randomized, double-blind, placebo-controlled, parallel group factorial study in patients with mild to severe hypertension was conducted to determine if treatment with telmisartan and amlodipine tablets was more effective in reducing blood pressure compared to the respective monotherapies. The study randomized 1461 patients with baseline systolic blood pressure between 117 and 179 mmHg (mean 153 mmHg) and a baseline diastolic blood pressure between 90 and 119 (mean 102 mmHg) to one of the 16 treatment arms. Patients assigned to receive amlodipine 10 mg started on amlodipine 5 mg or combinations thereof for the first 2 weeks. The four key treatment combinations (including combinations of telmisartan 40 or 80 mg and amlodipine 5 or 10 mg) had statistically significant reduction in in-clinic seated trough cuff systolic and diastolic blood pressure compared to the respective individual monotherapies (Table 5).

The majority of the antihypertensive effect of the telmisartan/amlodipine combination was attained within 2 weeks after initiation of therapy. In patients receiving a telmisartan/amlodipine combination, significantly larger reductions in seated diastolic and systolic blood pressure compared to patients treated with the respective monotherapies were observed at every assessment (Week 2, 4, 6, and 8). 

The antihypertensive effect of telmisartan and amlodipine tablets was similar in patients ≥ 65 years than below 65 years of age, in male and female patients, and in patients with and without diabetes. 

The magnitude of blood pressure lowering in black patients approached that observed in non-black patients but the number of black patients was limited (237 of 1461 patients). 

Automated ambulatory blood pressure monitoring (ABPM) performed in a subset of 562 patients confirmed the results seen with in-clinic systolic and diastolic blood pressure reductions over the entire 24-hour dosing period. 

In a double-blind, active-controlled study, a total of 1097 patients with mild to severe hypertension (mean baseline systolic/diastolic BP 149.5/96.6 mmHg) who were not adequately controlled on amlodipine 5 mg received telmisartan and amlodipine tablets (40/5 mg or 80/5 mg) or amlodipine alone (5 mg or 10 mg). After 8 weeks administration, each of the combination treatments was statistically significantly superior to both amlodipine monotherapy doses in reducing diastolic and systolic blood pressures. Edema related events (peripheral edema, generalized edema, and edema) in patients who received telmisartan and amlodipine tablets (40/5 mg or 80/5 mg) were significantly lower as compared to patients who received amlodipine 10 mg (4.3% vs 27.2%, respectively).

In a second double-blind, active-controlled study, a total of 947 patients with mild to severe hypertension (mean baseline systolic/diastolic BP 147.5/95.6 mmHg) who were not adequately controlled on amlodipine 10 mg received telmisartan and amlodipine tablets (40/10 mg or 80/10 mg) or amlodipine alone (10 mg). After 8 weeks, each of the combination treatments was statistically significantly superior to amlodipine monotherapy in reducing diastolic and systolic blood pressures.

There are no trials of telmisartan and amlodipine tablets demonstrating reductions in cardiovascular risk in patients with hypertension, but at least one pharmacologically similar drug has demonstrated such benefits.