Innovations, challenges, and gaps in the development of an effective vaccine against Neisseria gonorrhoeae, a narrative review.

Neisseria gonorrhoeae, the causative agent of gonorrhea, accounts for over 87 million new cases annually. It poses a serious threat to global health due to its high antimicrobial resistance. The development of an effective gonorrhea vaccine has been severely hampered by unique characteristics of this pathogen, particularly antigenic and phase variation of surface antigens. Additionally, the difficulty of eliciting effective mucosal immune responses and the inability of natural infection to produce long-lasting immunity further complicate vaccine development. In this review, the main obstacles to gonococcal vaccine development are discussed. Clinical trials evaluating the cross-protective effects (approximately 31-46 %) of 4CMenB vaccine against N. gonorrhoeae have been explored, along with recent advances such as recombinant proteins, multivalent and epitope-based approaches, and emerging mRNA platforms. Promising findings from preclinical studies are highlighted, together with growing role of artificial intelligence and machine learning in antigen discovery and vaccine optimization. Despite these innovations, translating theoretical approaches into safe, immunogenic, and broadly protective vaccines remains a major challenge. This review underscores the urgent need for continued interdisciplinary research to close existing gaps and develop a feasible efficient vaccine to combat drug-resistant gonorrhea.