Post-ischaemic administration of themurine Canakinumab-surrogate antibody improves outcome in experimental stroke

Aims The CANTOS trial underscored the efficacy of selective antibody-based interleukin (IL)-1 beta inhibition with Canakinumab in secondary prevention of cardiovascular events. Despite the success of the trial, incidence of stroke was not reduced likely due to the low number of events and the relatively young age of patients enrolled. Given the established role of IL-1 beta in stroke, we tested the efficacy of the murine Canakinumab-equivalent antibody in a mouse model of ischaemic stroke. To mimic the clinical scenario of modern stroke management, IL-1 beta inhibition was performed post-ischaemically upon reperfusion as it would be the case in patients presenting to the emergency room and eligible for thrombolytic therapy. Methods and results Transient middle cerebral artery occlusion (tMCAO) was performed in wild type mice; upon reperfusion, mice were randomly allocated to anti-IL-1 beta antibody or vehicle treatment. Following tMCAO, cerebral IL-1 beta levels, unlike tumour necrosis factor-alpha, were increased underscoring a role for this cytokine. Post-ischaemic treatment with IL-1 beta antibody reduced infarct size, cerebral oedema and improved neurological performance as assessed by 2,3,5-triphenyltetrazolium chloride staining, Bederson and RotaRod tests. Antibody-treated animals also exhibited a reduced neutrophil and matrix metalloproteinase (MMP)-2 but not MMP-9, activity in ipsilateral hemispheres as compared to vehicle-treated mice. Noteworthy, tMCAO associated vascular endothelial-cadherin reduction was blunted in IL-1 beta antibody-treated mice compared to vehicle-treated, likely providing the mechanistic explanation for the improved outcome. Conclusion Our data for the first time demonstrate the efficacy of selective post-ischaemic IL-1 beta blockade in improving outcome following experimental ischaemia/reperfusion brain injury in the mouse and encourage further focused clinical studies assessing the potential of the approved IL-1 beta antibody Canakinumab, as an adjuvant therapy to thrombolysis in acute ischaemic stroke patients.