Riprazo is a medicine that contains the active substance aliskiren. It is available as tablets (pink and round: 150 mg; red and oval: 300 mg).
|Table of Contents|
|What is it used for?|
|How is it used?|
|How does it work?|
|How has it been studied?|
|What benefits has it shown during the studies?|
|What is the risk associated?|
|Why has it been approved?|
Riprazo is used to treat essential hypertension (high blood pressure). ?Essential? means that the hypertension has no obvious cause.
The medicine can only be obtained with a prescription.
The recommended dose of Riprazo is 150 mg once a day, either taken alone or in combination with other medicines for hypertension. It should be taken with a light meal preferably at the same time each day, but grapefruit juice should not be taken together with Riprazo The dose of Riprazo may be increased to 300 mg once a day in patients whose blood pressure is not adequately controlled. Riprazo is not recommended for use in patients below 18 years of age, because of a lack of information on safety and effectiveness in this age group.
The active substance in Riprazo, aliskiren, is a renin inhibitor. It blocks the activity of a human enzyme called renin, which is involved in the production of a substance called angiotensin I in the body. Angiotensin I is converted into the hormone angiotensin II, which is a powerful vasoconstrictor (a substance that narrows blood vessels). By blocking the production of angiotensin I, levels of both angiotensin I and angiotensin II fall. This causes vasodilation (widening of the blood vessels), so that the blood pressure drops. This may reduce the risks associated with high blood pressure, such as having a stroke.
The effects of Riprazo were first tested in experimental models before being studied in humans. Riprazo was studied in 14 main studies involving over 10,000 patients with essential hypertension. Thirteen of the studies included patients with mild to moderate hypertension, and one included patients with severe hypertension. In five of the studies, the effects of Riprazo taken alone were compared with those of placebo (a dummy treatment). Riprazo, taken alone or in combination with other medicines, was also compared with other medicines for hypertension. Combination studies looked at Riprazo used with an angiotensin converting enzyme inhibitor (ramipril), an angiotensin receptor blocker (valsartan), a beta-blocker (atenolol), a calcium-channel blocker (amlodipine) and a diuretic (hydrochlorothiazide). The studies lasted between six and 52 weeks and the main measure of effectiveness was the change in blood pressure during either the resting phase of the heartbeat (?diastolic?) or when the chambers of the heart were contracting (?systolic?). The blood pressure was measured in ?millimetres of mercury? (mmHg).
Riprazo on its own was more effective than placebo and as effective as comparator treatments in reducing blood pressure. When the results of the five studies comparing Riprazo taken alone with placebo were looked at together, patients aged under 65 years had an average fall in diastolic blood pressure of 9.0 mmHg after eight weeks of taking 150 mg Riprazo, from an average of 99.4 mmHg at the start of the study. This was compared with a fall of 5.8 mmHg from 99.3 mmHg in the patients taking placebo.
Larger falls were seen in patients aged 65 years or over and those taking higher doses of Riprazo. Riprazo also reduced blood pressure in patients with diabetes and patients who were overweight. The medicine?s effects were maintained for up to a year in two of the studies.
The studies also showed that Riprazo, when taken in combination with other medicines (especially hydrochlorothiazide), can produce additional decreases in blood pressure compared with the decreases produced by these medicines when they are taken without Riprazo.
The most common side effect with Riprazo (seen in between 1 and 10 patients in 100) is diarrhoea. For the full list of all side effects reported with Riprazo, see the Package Leaflet.
Riprazo should not be used by people who may be hypersensitive (allergic) to aliskiren or any of the other ingredients. It must not be used in patients who have had angioedema (swelling under the skin) with aliskiren or in women who are more than three months pregnant. Its use during the first three months of pregnancy and in women planning to become pregnant is not recommended. Riprazo must also not be taken with ciclosporin (a medicine that reduces the activity of the immune system), quinidine (used to correct irregular heartbeat) or verapamil (used to treat heart problems).