A5: amlodipine 5 mg; A10: amlodipine 10 mg; T40: telmisartan 40 mg; T80: telmisartan 80 mg; TEAMSTA-5: telmisartan/amlodipine single-pill study to assess the efficacy in patients with essential hypertension not controlled on A5; TEAMSTA-10: telmisartan/amlodipine single-pill study to assess the efficacy in patients with essential hypertension not controlled on A10.