The dog large vessel occlusion (LVO) model mimics the clinical trend observed in patients where the brain infarct follows either a slow or fast progression. The dog LVO model can be used in the design of new therapeutics to improve clinical outcome in patients. This study examined the effect of an oxygen carrier in its ability to slow infarct growth in the dog LVO model. In fast evolvers, the oxygen carrier therapy prolonged infarct progression and reduced the final normalized infarct volume. Delaying infarct progression can potentially extend the time-window for thrombectomy enabling more patients to receive this critical treatment.