In 2001, the Food and Drug Administration (FDA) evaluated an application for the use of drotrecogin alfa (activated), or recombinant human activated protein C (Xigris, Eli Lilly), in patients with severe sepsis. The use of activated protein C, as compared with placebo, was associated with a significant reduction in mortality in the Recombinant Human Activated Protein C Worldwide Evaluation in Severe Sepsis (PROWESS) trial (24.7 percent vs. 30.8 percent, P=0.005).¹ Extensive review by physicians and scientists at the FDA confirmed the principal findings of the PROWESS trial but raised issues regarding the interpretation of data and appropriate use of the . . .