METALYSE should be prescribed by physicians experienced in the use of thrombolytic treatment and with the facilities to monitor that use. This does not preclude the pre-hospital use of METALYSE. As with other thrombolytics, it is recommended that when METALYSE is administered standard resuscitation equipment and medication be available in all circumstances. Coronary Intervention: Transfer to a coronary intervention capable facility for adjunctive Percutaneous Coronary Intervention (PCI): Patients receiving METALYSE as primary coronary recanalization treatment should be transferred without delay to a coronary intervention capable facility for angiography and timely coronary intervention within 6-24 hours or earlier if medically indicated (see Pharmacology under Actions).
Primary Percutaneous Coronary Intervention (PCI): If primary PCI is scheduled according to the current relevant treatment guidelines, METALYSE as administered in the ASSENT-4 PCI study (see Pharmacology under Actions) should not be given.
Bleeding: The most common complication encountered during METALYSE therapy is bleeding. The concomitant use of heparin anticoagulation may contribute to bleeding. As fibrin is lysed during METALYSE therapy, bleeding from recent puncture sites may occur. Therefore, thrombolytic therapy requires careful attention to all possible bleeding sites (including those following catheter insertion, arterial and venous puncture, cutdown and needle puncture). The use of rigid catheters, intramuscular injections and non-essential handling of the patient should be avoided during treatment with METALYSE.
Should serious bleeding occur, in particular cerebral haemorrhage, concomitant heparin administration should be terminated immediately. Administration of protamine should be considered if heparin has been administered within 4 hours before the onset of bleeding. In the few patients who fail to respond to these conservative measures, judicious use of transfusion products may be indicated. Transfusion of cryoprecipitate, fresh frozen plasma, and platelets should be considered with clinical and laboratory reassessment after each administration. A target fibrinogen level of 1 g/l is desirable with cryoprecipitate infusion. Antifibrinolytic agents should also be considered.
The use of METALYSE therapy has to be carefully evaluated in order to balance the potential risks of bleeding with expected benefits under the following conditions: Systolic blood pressure >160 mm Hg; recent gastro-intestinal or genitourinary bleeding (within the past 10 days); any known recent (within the past 2 days) intramuscular injection; advanced age, i.e. over 75 years; low body weight <60 kg; cerebrovascular disease; patients receiving oral anticoagulants treatment: The use of METALYSE may be considered when appropriate test(s) of anticoagulant activity for the product(s) concerned show no clinically relevant activity.
Arrhythmias: Coronary thrombolysis may result in arrhythmia associated with reperfusion. Reperfusion arrhythmias may lead to cardiac arrest, can be life threatening and may require the use of conventional antiarrhythmic therapies.
Glyco-Protein IIb/IIIa Antagonists: The concomitant use of GPIIb/IIIa antagonists increases the risk of bleeding.
Thromboembolism: The use of METALYSE can increase the risk of thrombo-embolic events in patients with left heart thrombus, e.g., mitral stenosis or atrial fibrillation.
Hypersensitivity: No antibody formation to the tenecteplase molecule has been observed after treatment. However, there is no experience with re-administration of METALYSE.
Anaphylactoid reactions associated with the administration of METALYSE are rare and can be caused by hypersensitivity to the active substance tenecteplase, gentamicin (a trace residue from the manufacturing process) or to any of the excipients. If an anaphylactoid reaction occurs, the injection should be discontinued and appropriate treatment should be initiated.
Impairment of Fertility: Clinical data as well as nonclinical studies on fertility are not available for tenecteplase (METALYSE).