Karvea is a medicine that contains the active substance irbesartan. It is available as white, oval tablets (75, 150 and 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?|
Karvea is used in patients who have essential hypertension (high blood pressure). ?Essential? means that the hypertension has no obvious cause. Karvea is also used to treat kidney disease in patients with hypertension and type 2 diabetes (non-insulin-dependent diabetes). Karvea 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 medicine can only be obtained with a prescription.
Karvea is taken by mouth, with or without food. The usual recommended dose is 150 mg once a day. If the blood pressure is not sufficiently controlled, the dose can be increased to 300 mg a day or other medicines for hypertension can be added, such as hydrochlorothiazide. A starting dose of 75 mg can be used in patients receiving haemodialysis (a blood clearance technique) or in patients over 75 years of age.
In patients with hypertension and type 2 diabetes, Karvea is added to other treatments for hypertension. Treatment is started at 150 mg once a day and is usually increased to 300 mg once a day.
The active substance in Karvea, irbesartan, is an ?angiotensin II receptor antagonist?, which means that it blocks the action of a hormone in the body called angiotensin II. Angiotensin II is a powerful vasoconstrictor (a substance that narrows blood vessels). By blocking the receptors to which angiotensin II normally attaches, irbesartan stops the hormone having an effect, allowing the blood vessels to widen. This allows the blood pressure to drop, reducing the risks associated with high blood pressure, such as having a stroke.
Karvea was originally studied in 11 trials for its effects on blood pressure. Karvea was compared with placebo (a dummy treatment) in 712 patients and with other medicines for hypertension (atenolol, enalapril or amlodipine) in 823 patients. Its use in combination with hydrochlorothiazide was also examined in 1,736 patients. The main measure of effectiveness was the reduction in diastolic blood pressure (the blood pressure measured between two heartbeats).
For the treatment of kidney disease, Karvea was studied in two large studies involving a total of 2,326 patients with type 2 diabetes. Karvea was used for two years or more. One study looked at markers of kidney damage by measuring whether the kidneys were releasing the protein albumin into the urine. The second study looked at whether Karvea increased the time taken until the patients? blood creatinine levels had doubled (a marker of kidney disease), until they needed a kidney transplant or dialysis, or until they died. In this study, Karvea was compared with placebo and with amlodipine.
In the blood pressure studies, Karvea was more effective than placebo at reducing diastolic blood pressure and had similar effects to the other medicines for hypertension. When used with hydrochlorothiazide, the effects of the two medicines were additive.
In the first kidney disease study, Karvea was more effective than placebo at reducing the risk of developing kidney damage as measured by protein excretion. In the second kidney disease study, Karvea reduced the relative risk of a doubling of blood creatinine levels, needing a kidney transplant, or death during the study by 20% in comparison with placebo. There was a 23% relative risk reduction compared with amlodipine. The main benefit was on the effect on blood creatinine levels.
The most common side effects with Karvea (seen in between 1 and 10 patients in 100) are dizziness, nausea (feeling sick) or vomiting, fatigue (tiredness) and increases in blood creatine kinase (an enzyme found in muscles). In addition, more than 1 patient in 100 with type 2 diabetes and kidney disease has the following side effects: hyperkalaemia (high blood potassium levels), orthostatic dizziness (dizziness when standing up), musculoskeletal (joint) pain and orthostatic hypotension (low blood pressure when standing up). For the full list of all side effects reported with Karvea, see the Package Leaflet.
Karvea should not be used in people who may be hypersensitive (allergic) to irbesartan or any of the other ingredients. It must not be used in women who are more than three months pregnant. Its use during the first three months of pregnancy is not recommended.
The Committee for Medicinal Products for Human Use (CHMP) decided that Karvea?s benefits are greater than its risks for the treatment of essential hypertension and of renal disease in patients with hypertension and type 2 diabetes mellitus. The Committee recommended that Karvea be given marketing authorisation.