The objective of this trial is to demonstrate that the fixed dose combination of telmisartan 40 mg and HCTZ 12.5 mg is superior to the monocomponent of telmisartan (Micardis, Gliosartan, Kinzal, Kinzalmono, Predxal, Pritor, Samertan, Telmisartan) 40 mg in patients with essential hypertension who fail to respond adequately to telmisartan monotherapy.