The Effects of Radioimmunotherapy and Antibiotics on Biofilm‐Associated Implant Infections in a Preclinical Rat Model

Lu-labeled 4497 antibody to S. aureus teichoic wall acid (WTA) (116.6 MBq/kg), or vancomycin (88 mg/kg), or combination of RIT (116.8 MBq/kg) and vancomycin, or left untreated. To evaluate efficacy, bacterial counts were taken from the joint capsule, bone, and implant after 7 days. Uptake and biodistribution were assessed via non-invasive in vivo SPECT/CT imaging and ex vivo gamma counting. Single administration of RIT achieved a 2.7-log (99.78%) reduction of bacterial burden in the infected joint capsule, had no effect on the infected femur, and resulted in 72.5% reduction of bacterial burden on the infected implant when compared to untreated controls. RIT reduced bacterial burden and inflammation in experimental PJI with no side effects. These findings underscore the potential of RIT in the treatment of infected indwelling devices and warrant further study.