As in Part I, patients in Part II will continue to be followed up for 21 days after their last dose of acadesine. If 1 out of the 3 patients experiences a DLT, a further 3 patients will be recruited to the cohort. If ≥ 2 patients out of the 6 experience a DLT, dosing will be stopped for this cohort and further cohorts of patients may be enrolled to receive up to 5 administrations of acadesine at a lower dose (or intermediate dose) over a 20 day period, based on safety, pharmacodynamic and pharmacokinetic data. The decision to continue at a lower dose will be based on a review by the DMB.