Treatment of Resistant Hypertension by Prevention of T-Cell Co-Stimulation

All subjects will be treated with chlorthalidone 25 mg/day, lisinopril 20 mg/day \[Patients with a history of adverse reaction to lisinopril will be treated with losartan 50 mg/day\], amlodipine 5 mg/day and spironolactone 25 mg bid as standardized treatment of hypertension prior to randomization and throughout the active treatment phase.

All subjects will be treated with chlorthalidone 25 mg/day, lisinopril 20 mg/day \[Patients with a history of adverse reaction to lisinopril will be treated with losartan 50 mg/day\], amlodipine 5 mg/day and spironolactone 25 mg bid as standardized treatment of hypertension prior to randomization and throughout the active treatment phase.