Exploration of Daptomycin Adsorption by Polymethylmethacrylate Hemofilter <i>In Vitro</i>

Blood purification therapy with cytokine-adsorbing hemofilters has been used to treat sepsis-associated hypercytokinemia. Polymethylmethacrylate (PMMA) hemofilters are frequently used for this purpose; however, adsorption and removal of teicoplanin, a therapeutic agent, have been reported. Similar concerns have been shared regarding daptomycin because its structure resembles that of teicoplanin; nevertheless, there have been no reported effects associated with daptomycin in this context. We studied the adsorption of daptomycin onto a PMMA hemofilter in vitro and investigated its adsorption onto hollow fiber membranes by adding cut PMMA membranes to a daptomycin solution. Additionally, the daptomycin solution was circulated in a dialysis circuit connected to a PMMA hemofilter, and changes in daptomycin content were examined. The daptomycin content decreased immediately after adding the hollow fiber membranes, similar to that observed for teicoplanin. The daptomycin content was lower than that of the standard reagent in the dialysis circuit model, reaching values below the measurement limit after 20 min. These results suggested that daptomycin was adsorbed and removed by the PMMA hemofilter. Encountering this effect during clinical use is plausible; therefore, daptomycin administration via a PMMA hemofilter should be avoided during blood purification therapy.