A Study to Compare COREG CR to COREG CR Fixed-dose Combination in Patients With High Blood Pressure

Inclusion criteria: * Adult males or females of non-child bearing potential who are between 18 and 60 years old. * Have a history of mild to moderate essential hypertension or present with mild to moderate essential hypertension defined by Diastolic Blood Pressure \>/90 and \</109 mmHg, and/or Systolic Blood Pressure \>/140 and \</179 mmHg * Body weight \> 60 kg (132 pounds) and body mass index (BMI) between 19 and 35 Exclusion criteria: * Any clinically relevant abnormality identified on the screening history, physical or laboratory examination, or any other medical condition or circumstances making the volunteer unsuitable for participation in the study. * History of advanced retinopathy (i.e., Keith-Wagener Grade III or IV) * Secondary forms of hypertension including (but not limited to) coarctation of the aorta, primary aldosteronism, renal artery stenosis, or pheochromocytoma * Type 1 diabetics \[note: Type 2 diabetics with HgbA1c less than or equal to 9.0% can be enrolled provided the Investigator considers the subject clinically stable\] * Signs, symptoms, or history of congestive heart failure, angina pectoris, myocardial infarction, cerebrovascular accident, or transient ischemic attacks * History or presence of clinically significant hepatic disease * Liver function tests (ALT, AST, total bilirubin or alkaline phosphatase) more than 2 times the upper limit of the laboratory reference range * History of severe pulmonary disease including asthma or chronic obstructive lung disease or previous history of 'hypersensitivity' to B-blockers * Previously treated hypertension in subjects in whom, at the discretion of the Investigator, antihypertensive therapy cannot be safely withdrawn during the study * Subjects who are on more than 3 antihypertensive or diuretic medications \[Note: combination antihypertensive and/or diuretic products (such as lisinopril and hydrochlorothiazide) should be considered as 2 medications, and the doses of each component should be recorded.\] * Subjects who metabolize carvedilol poorly based on CYP2D6 genotyping as determined at screening * History of regular alcohol consumption exceeding 7 drinks/week for women or 14 drinks/week for men (1 drink = 5 ounces of wine or 12 ounces of beer or 1.5 ounces of hard liquor) within 6 months of screening * Positive urine drug screen (UDS) including alcohol at screening. A minimum list of drugs that will be screened for include amphetamines, barbiturates, cocaine, opiates, cannabinoids and benzodiazepines. * Treatment with an investigational drug within 30 days or five half-lives, whichever is longer, prior to the first dose of study medication (this includes investigational formulations of marketed products) * Subjects receiving ongoing treatment or anticipated to receive treatment with any of the following medications during treatment with study medication: * monoamine oxidase (MAO) inhibitors * any Class I or III antiarrhythmic * alpha-adrenergic receptor blockers * beta-2-adrenergic receptor agonists * lithium * Consumption of grapefruit or grapefruit juice within 7 days prior to dosing * Women of child-bearing potential * NOTE: Pre-menopausal females with a documented tubal ligation or hysterectomy are eligible. Postmenopausal females are eligible, defined as 12 months of spontaneous amenorrhea \[in questionable cases a blood sample with simultaneous follicle stimulating hormone (FSH) \> 40 MlU/ml and estradiol \< 40 pg/ml (\<140 pmol/L) is confirmatory\]. * Resting pulse rate of ≤ 50 beats per minute (bpm) at screening * QTc ≥ 450 msec * ECG criteria as defined in protocol * Refusal or inability to discontinue use of medications known to be inhibitors/inducers of cytochrome P-450 2C9, 2D6 and 3A4 for at least 14 days or 5 half-lives \[which ever is longer\] prior to Day 1 of Session 1 and until 48 hours after the last dose of study medication. \[Examples include: paroxetine, isoniazid, "azole"antifungal drugs (e.g. itraconazole), erythromycin, ticlopidine, amiodarone, quinidine, rifampin, phenobarbital\] * Donation of blood in excess of 500 mL within a 56-day period including the estimated 210 mL of blood to be drawn during this study * History of sensitivity to carvedilol, lisinopril, alpha-blockers, beta-blockers or ACE inhibitors * History of sensitivity to heparin, heparin-induced thrombocytopenia, or sensitivity to any of the study medications or components thereof * History of angioedema * Positive for Hepatitis B surface antigen * Positive for HIV * Unwillingness or inability to follow the procedures outlined in the protocol or inability to provide written informed consent