Polymyxin B-immobilized fiber column ineffective for septic shock

Abstract

Polymyxin B, an antibiotic with high affinity for endotoxin, has been bound and immobilized to polystyrene fibers (PMX-DHP) in a medical device for hemoperfusion that was developed in Japan. Since PMX-DHP has become the insurance adaptation in Japan at an early stage, high quality clinical study had not been performed. Relatively large-scale 3 randomized controlled trials (RCTs) were performed abroad to date for the patients with septic shock to evaluate the reduction of mortality. Although one RCT showed significant difference in mortality compared with standard care, one RCT did not have significant difference. The result of last RCT was press-released that reported no significant difference in mortality of primary outcome in all cases, but significant difference in mortality in post-hoc, subgroup analysis. Nowadays, since standard management of sepsis has been distributed, and the mortality of sepsis has been decreased, it has been getting more difficult to prove significant difference in mortality. That indicates many therapies such as PMX-DHP, are effective in only very limited septic patients, therefore, indications of these therapies should be considered very carefully.