Metalyse

Metalyse is a powder and a solvent that are made up into a solution for injection. It contains the active substance tenecteplase.

Metalyse is used to treat adults suspected of having an acute myocardial infarction (heart attack) within six hours of the first symptoms appearing. It is used to dissolve the blood clots that have formed inside the blood vessels supplying the heart.

The medicine can only be obtained with a prescription.

Metalyse should be prescribed by doctors who have experience in the use of thrombolytic treatments (treatments to dissolve blood clots). Treatment with Metalyse should be started as soon as possible after the start of heart attack symptoms. Metalyse is given once as a single injection into a vein over around 10 seconds. The dose to be given is adjusted according to the patient’s weight (see the package leaflet).

In addition to Metalyse, the patient should also be treated with other medicines that are used to prevent blood clots such as aspirin and heparin.

The active substance in Metalyse, tenecteplase, is a modified copy of the human enzyme ‘tissue plasminogen activator’, which the body uses to break down clots. It works by converting a protein in the clots called plasminogen into its active form, plasmin, which breaks down the fibrous protein holding the clot together. With the blood clot broken down, blood can flow more easily into the heart muscle, allowing the heart to keep working and helping to save the patient’s life.

Tenecteplase 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.

Metalyse was compared with alteplase (another medicine used to treat heart attacks) in one main study involving about 17,000 adults who were having a heart attack. The patients were given either medicine within six hours of their symptoms appearing in addition to either aspirin or heparin. The main measure of effectiveness was the number of patients who were alive 30 days after treatment.

Metalyse was as effective as alteplase in keeping patients alive after a heart attack. Around 94% of patients who received either medicine were alive 30 days after treatment.

The most common side effect with Metalyse was haemorrhage (bleeding). The most common bleedings (seen in between 1 and 10 patients in 100) are epistaxis (nosebleeds), gastrointestinal haemorrhage (bleeding in the stomach or gut), ecchymosis (bleeding beneath the skin), urogenital haemorrhage (bleeding from the structures that carry urine or from the genital area), bleeding at the injection site, and bleeding at puncture site. For the full list of all side effects reported with Metalyse, see the package leaflet.

Metalyse should not be used in people who have had an anaphylactic reaction (a severe, life-threatening allergic reaction) to tenecteplase, gentamicin (an ingredient found in the medicine) or any of the other ingredients. If treatment is necessary in these patients, facilities for resuscitating them must be readily available. Metalyse should not be used 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.

The CHMP noted that while Metalyse was as effective as alteplase in preventing death, it caused less serious bleeding, which meant that fewer blood transfusions were required. Based on this and all other available data, the Committee decided that Metalyse’s benefits are greater than its risks and recommended that it be given marketing authorisation.

The European Commission granted a marketing authorisation valid throughout the European Union for Metalyse on 23 February 2001.

For more information about treatment with Metalyse, read the package leaflet (also part of the EPAR) or contact your doctor or pharmacist.