The purpose of this investigation is to determine if intraosseous infusion (IO) is a suitable method for the delivery of recombinant human factor VIIa (rFVIIa) during hemorrhagic shock. The measures that were used to evaluate IO delivery suitability included: (1) determination of clinically significant local or systemic toxicity and (2) demonstration that systemic blood levels of rFVIIa increased rapidly following administration. Our results indicate that there was no evidence of significant local or systemic toxicity following infusion and that the systemic blood concentration of rFVIIa peaks immediately after the end of infusion. This result suggests that the systemic blood level profiles of rFVIIa delivered by IO infusion are similar to those that could be produced by intravenous (IV) administration. Furthermore, in all 25 test animals, access to the systemic circulation during shock was achieved as evidenced by rapid increase in a marker dye (flourescein) or rFVIIa in the blood. We conclude that administration of rFVIIa via IO infusion is a reasonable safe method and is likely to produce blood levels required for improved hemostasis during shock.