In Part I of the study, blood samples for PK analysis (for both acadesine and its metabolite ZMP) will be taken pre-dose and 0, 30, 60 minutes, 2, 6, 20, 72, 96, and 168 hours, 14 and 21 days post-dose in all cohorts. Predictive modelling of repeat dose pharmacokinetics will be carried out and used in conjunction with the safety and pharmacodynamic data to predict a suitable multiple dose regimen in Part II of the clinical study, where up to 5 doses will be administered at regular intervals over a period of up to 20 days. The Part II dosing decision will be based on a review of the data by the DMB.