Metalyse is a vial containing a white powder and a prefilled syringe containing a solvent, to make up a solution for injection. Metalyse contains the active substance tenecteplase.
|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?|
Metalyse is used in patients to dissolve the blood clots that have formed in the vessels of the heart in patients who are suspected of having had an acute myocardial infarction (heart attack). Metalyse is used within 6 hours of the first symptoms of the heart attack.
The medicine can only be obtained with a prescription.
Metalyse should be prescribed by doctors who have experience in the use of thrombolytic treatment. Treatment with Metalyse should be started as soon as possible after the start of heart attack symptoms. Metalyse is given as a single intravenous (into a vein) injection over about 10 seconds. The doses are adjusted according to the patient?s weight (see the Package Leaflet). It is given with other medicines (aspirin, heparin) that prevent blood clots.
Metalyse is a thrombolytic (also known as a fibrinolytic, as it dissolves blood clots, which are made out of a substance called fibrin). The active substance in Metalyse, tenecteplase, is a modified form of the natural enzyme, human plasminogen activator. It is made by a method known as ?recombinant DNA technology?: it is made by a cell that has received a gene (DNA), which makes it able to produce it. Tenecteplase is a plasminogen activator, this means that it triggers the transformation of a substance (plasminogen) into plasmin. Plasmin breaks up clots. In myocardial infarction, clots have formed in the arteries to the heart. Metalyse dissolves the blood clots and helps restore the normal blood flow to the heart.
The effectiveness of Metalyse has been studied in a large trial (ASSENT II) in about 17,000 patients. Metalyse as an injection has been compared with alteplase (an exact copy of the human tissue plasminogen activator made using recombinant technology) as an infusion (drip into a vein). The studies examined the rate of death 30 days after treatment, and the rate of bleeding.
Metalyse was as effective as alteplase in reducing death at 30 days ? both treatments reduced death rate to about 6.2%. Metalyse caused significantly less non-intracranial (non-brain) major bleedings than alteplase, which meant that there was less need for blood transfusions.
The main side effect of Metalyse is bleeding, generally at the site of the injection. It can also give patients low blood pressure, irregular heart beats and chest pain. These side effects are seen in more than 1 patient in 10. In less than 1 patient in 100 bleeding in the brain can occur (cerebral haemorrhage), and this can cause death or permanent disability. For the full description of the side effects reported with Metalyse, please see the Package Leaflet.
Metalyse should not be used in people who may be hypersensitive (allergic) to tenecteplase or any of the other ingredients, or in patients who have or have had recent bleeding problems or major surgery, or have a disease which may cause bleeding (such as a past stroke or severe high blood pressure). For the full list of restrictions, see the Package Leaflet.