Similar outcomes were observed when erythropoietin was combined with TH, with the High-dose Erythropoietin for Asphyxia and Encephalopathy (HEAL) study concluding that there was no significant reduction in death or neurodevelopmental impairment at 2–3 years of age and that the treatment was associated with serious adverse events in infants with moderate-to-severe HIE55. This evidence concerns the gene EPO and asphyxia.