Background Antimicrobial resistance (AMR) poses a global health threat, particularly in low- and middle-income
countries (LMICs). Clustered regularly interspaced short palindromic repeats (CRISPR)–Cas system technology offers
a promising tool to combat AMR by targeting and disabling resistance genes in WHO bacterial priority pathogens.
Thus, we systematically reviewed the potential of CRISPR–Cas technology to address AMR.
Methods This systematic review adhered to the Preferred Reporting Items for Systematic Reviews and Meta-Anal‑
yses (PRISMA) guidelines. A comprehensive literature search was conducted using the Scopus and PubMed data‑
bases, focusing on publications from 2014 to June 2024. Keywords included “CRISPR/Cas,” “antimicrobial resistance,”
and“pathogen.” The eligibility criteria required original studies involving CRISPR/Cas systems that targeted AMR. Data
were extracted from eligible studies, qualitatively synthesized, and assessed for bias using the Joanna Briggs Institute
(JBI)-standardized tool.
Results Data from 48 eligible studies revealed diverse CRISPR–Cas systems, including CRISPR–Cas9, CRISPR–Cas12a,
and CRISPR–Cas3, targeting various AMR genes, such as blaOXA-232, blaNDM, blaCTX-M, ermB, vanA, mecA, fosA3,
blaKPC, and mcr-1, which are responsible for carbapenem, cephalosporin, methicillin, macrolide, vancomycin, colistin,
and fosfomycin resistance. Some studies have explored the role of CRISPR in virulence gene suppression, includ‑
ing enterotoxin genes, tsst1, and iutA in Staphylococcus aureus and Klebsiella pneumoniae. Delivery mechanisms
include bacteriophages, nanoparticles, electro-transformation, and conjugative plasmids, which demonstrate high
efficiency in vitro and in vivo. CRISPR-based diagnostic applications have demonstrated high sensitivity and specificity, with detection limits as low as 2.7× ­102 CFU/mL, significantly outperforming conventional methods. Experimental
studies have reported significant reductions in resistant bacterial populations and complete suppression of the tar‑
geted strains. Engineered phagemid particles and plasmid-curing systems have been shown to eliminate IncF plas‑
mids, cured plasmids carrying vanA, mcr-1, and blaNDM with 94% efficiency, and restore antibiotic susceptibility. Gene
re-sensitization strategies have been used to restore fosfomycin susceptibility in E. coli and eliminate blaKPC-2-me‑
diated carbapenem resistance in MDR bacteria. Whole-genome sequencing and bioinformatics tools have provided
deeper insights into CRISPR-mediated defense mechanisms. Optimization strategies have significantly enhanced
gene-editing efficiencies, offering a promising approach for tackling AMR in high-priority WHO pathogens.
Conclusions CRISPR–Cas technology has the potential to address AMR across priority WHO pathogens. While
promising, challenges in optimizing in vivo delivery, mitigating potential resistance, and navigating ethical-regulatory
barriers must be addressed to facilitate clinical translation.