In this trial, patients with severe sepsis and low protein C levels will receive drotrecogin alfa (activated) at the normal, approved dose and time of administration [24 microgram/kilogram/hour (mcg/kg/hour) for 96 hours] or will receive the normal, approved dose or higher doses than the approved dose for a longer administration time. After the drug administration is complete, the protein C levels from the patients receiving the normal, approved dose will be compared to protein C levels from patients receiving the normal, approved dose or higher dose for a longer duration to determine if the protein C levels improve faster if given higher dose and/or longer administration time.