Exploring Human Use of Monoclonal Antibodies Against Critical Bacteria: A Scoping Review of Clinical Trials.

Introduction: The global spread of multidrug-resistant organisms (MDROs), particularly the World Health Organization (WHO) priority pathogens, poses a major challenge to infection treatment, necessitating alternative therapeutic strategies. Monoclonal antibodies (mAbs) have emerged as a potential approach. This review evaluates the clinical efficacy, safety, and limitations of mAbs targeting critical bacterial pathogens, analyzing factors influencing therapeutic outcomes, and proposing strategies to optimize their clinical application.

Methods: A comprehensive analysis of clinical trials investigating antibacterial mAbs was conducted. The review assessed key factors influencing therapeutic outcomes, including trial design, patient heterogeneity, and pharmacokinetics (PK). Comparative analysis was performed to examine differences in efficacy, safety, and limitations across studies. A structured risk of bias assessment was performed using Cochrane Methods' tools.

Results: Owing to the low number of studies against MDROs, all trials about mAbs targeting Staphylococcus aureus (SA) and Pseudomonas aeruginosa (PA) were included, disregarding resistance profiles. Generally, clinical trials evaluating antibacterial mAbs have shown preliminary evidence. For PA, panobacumab exhibited a favorable safety profile but lacked clear clinical benefits, showing a good survival rate but in a small uncontrolled trial. Rivabazumab reduced bacterial colonization, but did not significantly lower pneumonia incidence. Gremubamab was well tolerated but failed to meet efficacy endpoints. For SA, tosatoxumab and suvratoxumab failed to show statistical significance but may have potential benefits for pneumonia, although phase III trials are needed.

Conclusions: Inconsistent efficacy may stem from complex host-pathogen interactions, biofilm formation, and variations in patient immune status. Future trials should investigate early mAb administration, stratified patient selection, and standardized antibiotic coadministration, poorly addressed thus far. Optimized dosing and mAb combination regimens are promising yet unexplored paths, while high production costs and regulatory issues remain a significant barrier.