Issues in the adjunct therapy of severe sepsis

Until recently the concept of immunomodulation in patients with severe sepsis (formerly called sepsis syndrome or septic shock) appeared very promising. Research has focused on the possible therapeutic potential of interfering with cytokine pathways, either by preventing the induction of cytokines, such as TNF-a, by neutralization of lipopolysaccharide (LPS), or through the use of agents that attenuate cytokine action. Nowadays research on protein or protein constructs with antibacterial activities such as bacterial/permeability increasing protein (BPI), platelet activating factor receptor antagonists, nitric oxide and cyclo-oxygenase inhibitors, are still being followed. In large clinical trials monoclonal antibodies against core glycolipid (E5, HAIA) were shown to be at best of only marginal benefit, and in some trials results were indecisive. Also, the results with IL-lra, although initially heralded with high expectation, were at the end disappointing and the trials discontinued. Two large trials with monoclonal antibodies against TNF showed some effect in subcategories of patients; a third trial is on its way. Other phase I, II studies include those of soluble TNF receptors and BPI. The area of immunomodulation has now become an area of more realism and the results of early trials has forced investigators to go back to the drawing board and to re-investigate the whole concept of immunotherapy and immunoprophylaxis.