Active Substance: anagrelide
Common Name: anagrelide
ATC Code: L01XX35
Marketing Authorisation Holder: Shire Pharmaceutical Contracts Limited
Active Substance: anagrelide
Authorisation Date: 2004-11-16
Therapeutic Area: Thrombocythemia, Essential
Pharmacotherapeutic Group: Antineoplastic agents
Xagrid is indicated for the reduction of elevated platelet counts in at-risk essential-thrombocythaemia (ET) patients who are intolerant to their current therapy or whose elevated platelet counts are not reduced to an acceptable level by their current therapy.
An at-risk patient
An at-risk ET is defined by one or more of the following features:
- >60 years of age or;
- a platelet count >1000 x 109/l or;
- a history of thrombohaemorrhagic events.
What is Xagrid?
Xagrid is a medicine that contains the active substance anagrelide. It is available as capsules (0.5 mg).
What is Xagrid used for?
Xagrid is used to reduce the number of platelets (components that help the blood to clot) in patients with essential thrombocythaemia (a disease in which there are too many platelets circulating in the blood). ‘Essential’ means that the disease has no obvious cause. Xagrid is used when patients do not respond to or do not tolerate their current treatment, and when they are ‘at risk’ because of their age (over 60 years), very high platelet counts or previous clotting problems.
Because the number of people with essential thrombocythaemia is low, the disease is considered ‘rare’, and Xagrid was designated an ‘orphan medicine’ (a medicine used in rare diseases) on 29 December 2000.
The medicine can only be obtained with a prescription.
How is Xagrid used?
Treatment with Xagrid should only be started by a doctor who has experience in the treatment of essential thrombocythaemia.
The recommended starting dose of Xagrid is one capsule twice a day. After a week, the dose is increased every week by one capsule a day, until the patient achieves a platelet count below 600 million platelets per millilitre, and ideally between 150 and 400 million/ml (the level usually seen in healthy people). Results are normally seen within two or three weeks of starting treatment.
The maximum recommended dose of Xagrid is five capsules at a time. Doses of up to 20 capsules a day were used during the development and testing of the medicine.
How does Xagrid work?
Essential thrombocythaemia is a disease in which the bone marrow produces too many platelets. This puts the patient at risk of developing blood clots or bleeding problems. The active substance in Xagrid, anagrelide, blocks the development and growth of cells in the bone marrow called ‘megakaryocytes’, which produce platelets. This reduces the platelet count, helping to improve symptoms in patients with the disease.
How has Xagrid been studied?
Xagrid has been studied in four main studies involving patients with various diseases in which the bone marrow produces too many cells. Almost 3,000 of the patients in the studies had essential thrombocythaemia, defined as a platelet count of more than 600 million/ml. Most patients had previously received other medicines but needed to change treatment. Xagrid was not compared with any other medicines. Patients were treated with Xagrid for up to five years. The main measure of effectiveness was the number of patients who had a ‘complete response’, defined as a reduction in platelet counts of at least 50% from the start of treatment or to below 600 million/ml.
What benefit has Xagrid shown during the studies?
Xagrid was effective in lowering platelet counts. In the largest study, 67% of the patients with essential thrombocythaemia (628 out of 934), and 66% of those who could not tolerate or did not respond to other treatments (480 out of 725) had a complete response to Xagrid. The number of clotting and bleeding problems experienced by the patients fell during the studies, but the benefit of this was not shown convincingly.
What is the risk associated with Xagrid?
The most common side effect with Xagrid (seen in more than 1 patient in 10) is headache. For the full list of all side effects reported with Xagrid, see the package leaflet.
Xagrid must not be used in patients with moderate or severe liver or kidney disease. For the full list of restrictions, see the package leaflet.
Why has Xagrid been approved?
The CHMP concluded that Xagrid had shown its effectiveness in lowering platelet counts in patients with essential thrombocythaemia. The Committee decided that Xagrid’s benefits are greater than its risks as second-line treatment in at-risk patients with essential thrombocythaemia. The Committee recommended that Xagrid be given marketing authorisation.
Xagrid has been authorised under ‘exceptional circumstances’. This means that, because the disease is rare, it has not been possible to obtain complete information about Xagrid. Every year, the European Medicines Agency will review any new information that may become available and this summary will be updated as necessary.
What information is still awaited for Xagrid?
The company that markets Xagrid will regularly inform the CHMP of all information published on the effectiveness of the medicine.
Other information about Xagrid
The European Commission granted a marketing authorisation valid throughout the European Union for Xagrid on 16 November 2004.
For more information about treatment with Xagrid, read the package leaflet (also part of the EPAR) or contact your doctor or pharmacist.
Source: European Medicines Agency
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