Because lipopolysaccharides are potent inflammatory agents, and the action of antibiotics can result in the release of these compounds, the binding capacity of BPI was explored as a possible means of reducing injury. Xoma Ltd. developed a recombinant 25kDa portion of the BPI molecule called rBPI21, NEUPREX, or opebecan. In a trial, it was found to decrease the mortality of Gram-negative bacterial-induced sepsis. Studies suggest that its binding activity is not the means by which it mediates its protective effect. Studies show biological effects with Gram-positive bacteria and even in infection by the protozoan, Toxoplasma gondii.
^G Schlag; H Redl, J Davies, and P Scannon (February 1999). "Protective effect of bactericidal/permeability-increasing protein (rBPI21) in baboon sepsis is related to its antibacterial, not antiendotoxin, properties". Annals of Surgery (US: Lippincott Williams & Wilkins) 229 (2): 262–271. doi:10.1097/00000658-199902000-00015. ISSN0003-4932. PMC1191640. PMID10024109.
^Amit Srivastava; Heather Casey, Nathaniel Johnson, Ofer Levy, and Richard Malley (January 2007). "Recombinant Bactericidal/Permeability-Increasing Protein rBPI21 Protects against Pneumococcal Disease". Infection and Immunity (US: American Society for Microbiology) 75 (1): 342–349. doi:10.1128/IAI.01089-06. ISSN0019-9567. PMC1828387. PMID17101667.