2 The technology
2.1 Alteplase (Actilyse, Boehringer Ingelheim) is a tissue plasminogen activator manufactured by recombinant DNA technology. It activates the production of plasmin from its precursor plasminogen. Plasmin is an enzyme that degrades fibrin clots. The aim of treatment is to reduce the impact of ischaemia by restoring blood flow through the occluded (blocked) artery. A UK marketing authorisation for alteplase to treat acute ischaemic stroke within 3 hours of the onset of symptoms was granted in September 2002. On 14 March 2012 the manufacturer received approval from the Medicines and Healthcare products Regulatory Agency extending the use of alteplase to within 4.5 hours of the onset of symptoms. The current marketing authorisation states that treatment must be started as early as possible within 4.5 hours after onset of stroke symptoms and after exclusion of intracranial haemorrhage by appropriate imaging techniques.
2.2 The summary of product characteristics lists the following adverse reactions for alteplase: haemorrhage (intracranial and gastrointestinal), recurrent ischaemia or angina, hypotension, heart failure, pulmonary oedema and reperfusion arrhythmias. For full details of adverse reactions and contraindications, see the summary of product characteristics.
2.3 The cost of alteplase is £135 per 10-mg pack, £180 per 20-mg pack and £300 per 50-mg pack (excluding VAT; 'British national formulary' [BNF] edition 63). The cost per course of treatment depends on the body weight of the patient, and can range from £300 to £600 based on a recommended dose of 0.9 mg per kilogram of body weight. Costs may vary in different settings because of negotiated procurement discounts.