Effective mitigation of total body irradiation damage in C57BL/6NHsd mice by intravenous administration of JP4-039. Experiments shown are over a course of a year accounting for the TBI dose “drift” of the LD50/30. At 3 different time points during a single calendar year, experiments were carried out delivering JP4-039/F15 in 100 μL volume containing 20 mg/kg drug, to mice. In these experiments, the LD50/30 was noted to “drift” over the course of the year and could not be explained by changes in the Cesium-70 Gamma Cell irradiator, supplier of mice, age of mice, gender of mice (all were female), diet, or other factors in the animal care facility. In all experiments, despite the “drift” of the LD50/30, JP4-039 was an effective mitigator against total body irradiation.