Neonatal hypoxic-ischemic encephalopathy (HIE) is a major cause of death or long-term disability in infants born at term in the western world, affecting about 1-4 per 1.000 life births and consequently about 5-20.000 infants per year in Europe.Hypothermic treatment became the only established therapy to improve outcome after perinatal hypoxic-ischemic insults. Despite hypothermia and neonatal intensive care, 45-50% of affected children die or suffer from long-term neurodevelopmental impairment. Additional neuroprotective interventions, beside hypothermia, are warranted to further improve their outcome.Allopurinol is a xanthine oxidase inhibitor and reduces the production of oxygen radicals and brain damage in experimental, animal, and early human studies of ischemia and reperfusion.This project aims to evaluate the efficacy and safety of allopurinol administered immediately after birth to near-term infants with HIE in addition to hypothermic treatment.Beyond this primary objective, the project will provide information on the effect of hypothermia on pharmacokinetics of drugs with a similar metabolism as allopurinol in neonates. Furthermore it will give the opportunity to further develop and validate biomarkers for neonatal brain injury using advanced magnetic resonance imaging, biochemistry, and electroencephalogramms, which will then be available for future studies testing neuroprotective interventions. Finally, this trial will extend our knowledge about incidence of and risk factors for perinatal asphyxia and HIE possibly enabling generation of more preventive strategies for the future.