Antimicrobial Peptides Against ESKAPE Pathogens: Mechanisms, Molecular Optimization, and Current Limitations

ESKAPE pathogens represent a priority clinical threat due to their multidrug-resistance, persistence in biofilms, and ability to evade antibiotic therapy. In response to these limitations, antimicrobial peptides (AMPs) have emerged as promising platforms for the development of novel anti-infective strategies. This review analyzes the potential of AMPs against ESKAPE pathogens, integrating their main classes, mechanisms of action, design strategies, and barriers to clinical translation. Natural, synthetic, and peptidomimetic AMPs are examined, along with lytic mechanisms, intracellular targets, anti-virulence effects, quorum quenching, and immunomodulation. In addition, in silico design approaches, multi-objective prediction, and molecular optimization strategies—including stereochemical modifications, cyclization, lipidation, PEGylation, and hybrid design—are discussed. Finally, their activity against ESKAPE biofilms is addressed, together with current limitations related to stability, toxicity, delivery, and preclinical validation.