Inclusion Criteria:

• Mild to moderate hypertension (sitting DBP > 95 - <114 mmHg and/or SBP > 140 - < 160 mmHg) currently untreated. or
• Previously diagnosed mild to moderate hypertension (DBP 95-114 mmHg and/or SBP 140 - 160 mmHg) well controlled on current treatment but experiencing adverse events who can be safely switched to the study treatments. or
• Previously diagnosed mild to moderate hypertension (DBP 95-114 mmHg and/or SBP 140 - 160 mmHg), well controlled on current treatment, without adverse events, and willing to participate in the study.

Exclusion Criteria:

• Females who are pregnant, nursing or of childbearing age, unless sterilised. Subjects receiving any form of contraception are not eligible.
• Subjects with a medical history of cardiac disease within 6 months (e.g. myocarditis or pericarditis, aortic stenosis, myocardial infarction, unstable angina pectoris or severe angina pectoris).
• Subjects with history or evidence of congestive heart failure
• Subjects with evidence of clinically important arrhythmia or conduction disturbances requiring treatment.
• Subjects with severe liver disease (liver enzymes twice the upper limit of "normal") or other gastrointestinal (GI) tract diseases including inflammatory bowel disease or Crohn's disease
• Subjects with lactose intolerance.
• Subjects with renal diseases (creatinine > 1.5 mg/dL), which could alter the absorption, metabolism or excretion of the study drugs.
• Subjects with Type I diabetes.
• Subjects taking drugs which may interfere with the metabolism of nifedipine (cimetidine, ranitidine, quinidine, digoxin, rifampicin, diltiazem, cisapride, quinupristin/dalfopristin, cyclosporin, phenytoin or other antiepileptic drugs,).
• Subjects suffering from secondary or malignant hypertension.
• Subjects with any known contraindication (e.g. hypersensitivity) to nifedipine or other calcium channel blockers of the dihydropyridine class.
• Subjects with previously known clinically significant abnormalities of laboratory tests that might suggest further investigation.
• Subjects with a resting heart rate < 50 bpm or > 100 bpm.
• Subjects with a history of drug and/or alcohol abuse.
• Subjects unwilling to comply with the protocol.
• Subjects who have participated in another clinical trial within the last month.
• Subjects with neurologic or psychiatric illness requiring medication (e.g. tricyclic antidepressants, MAO inhibitors).
• Subjects with clinical evidence of ongoing or recent (within the last year) stroke or transient ischemic attacks.
• Subjects with pre-existing severe gastrointestinal or oesophageal constriction or narrowing.