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.