Antimicrobial resistance in Neisseria gonorrhoeae: Tipping point between therapeutic failure and scientific innovation
– by Teodora Elvira C. Wi

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Introduction: A narrowing window for action

For nearly a century, Neisseria gonorrhoeae has demonstrated a remarkable evolutionary ability to evade every major antimicrobial introduced for its treatment. Since the antibiotic era began, the gonococcus has repeatedly rendered once-effective therapies obsolete, transforming gonorrhoea into one of the world’s most formidable antimicrobial-resistant pathogens.¹

The emergence of multidrug-resistant (MDR) and extensively drug-resistant (XDR) strains threatens the effectiveness of the last-line therapies^2,3 and raises an urgent question: Are we approaching an era of untreatable gonorrhoea, or can scientific innovation change the trajectory of one of the oldest sexually transmitted infections (STIs)? The answer depends on whether the global community acts with sufficient urgency and scale.

Antimicrobial resistance (AMR) in N. gonorrhoeae is not merely another example of bacterial resistance. It threatens decades of progress in sexual and reproductive health, HIV prevention, maternal and child health and global antimicrobial stewardship.

Without equitable access to diagnostics, new therapies and surveillance, gonococcal AMR will further widen global health inequities.

N. gonorrhoeae remains one of the most common bacterial STIs worldwide, with the World Health Organization (WHO) estimating more than 82 million new infections annually.⁴ Untreated or inadequately treated gonococcal infection can lead to pelvic inflammatory disease, tubal infertility, ectopic pregnancy, chronic pelvic pain, epididymitis and disseminated gonococcal infection.⁵ During pregnancy, gonorrhoea is associated with preterm birth, premature rupture of membranes, low birth weight, and neonatal infections.⁶ Vertical transmission remains an important cause of neonatal conjunctivitis and blindness. As treatment failures increase, so too does the risk to fertility, maternal health, and newborn survival.

The consequences extend beyond STI control. Gonococcal infection increases HIV acquisition and transmission by inducing mucosal inflammation and increasing genital shedding of the virus, potentially undermining progress towards ending AIDS as a public health threat.⁷

The burden of drug-resistant gonorrhoea is unequally distributed. Adolescents, young women, key populations and other marginalized communities are disproportionately affected, making its consequences significant for individual health and societal well-being.⁸ Low- and middle-income countries (LMICs), where diagnostic and surveillance systems remain weakest, are likely to bear the greatest burden.⁹ Without equitable access to diagnostics, new therapies and surveillance, gonococcal AMR will further widen global health inequities.

If the global community cannot preserve effective treatment for one of the closely monitored bacterial pathogens, it raises broader concerns about our ability to address AMR in less- surveilled organisms. Thus, the emergence of ceftriaxone resistance should be interpreted not as an isolated STI concern but as a global health security issue.

N.gonorrhoeae possesses a unique ability to rapidly acquire and disseminate resistance determinants through chromosomal mutations and horizontal gene transfer.^1,3 Historically, resistance emerged locally before spreading internationally through travel, migration, and interconnected sexual networks. The recent emergence of ceftriaxone- resistant strains in Asia, together with increasing reports of treatment failure in Europe and Australia, suggests that this pattern is repeating itself.^9-14 Drug-resistant gonorrhoea therefore serves as a sentinel pathogen, exposing weakness in antimicrobial stewardship, surveillance and global preparedness for AMR.

If the global community cannot preserve effective treatment for one of the closely monitored bacterial pathogens, it raises broader concerns about our ability to address AMR in less- surveilled organisms. Thus, the emergence of ceftriaxone resistance should be interpreted not as an isolated STI concern but as a global health security issue.

From successive therapeutic losses to ceftriaxone threat

The history of gonorrhoea treatment mirrors the history of AMR itself. Sulfonamides revolutionized treatment in the 1930s but became ineffective within a decade. Penicillin subsequently transformed gonorrhoea management and remained highly effective for several decades until penicillinase-producing N. gonorrhoeae strains emerged in the 1970s.¹⁵ Resistance to tetracyclines soon followed, and by the late 1990s widespread resistance to fluoroquinolones, particularly ciprofloxacin, had rendered another important therapeutic option ineffective.¹⁶ Extended-spectrum cephalosporins, particularly cefixime and ceftriaxone together with the macrolide, azithromycin, became the final therapeutic options. However, reduced susceptibility and treatment failure have been increasingly documented.^2-3,11

Data from the WHO Enhanced Gonococcal Antimicrobial Surveillance Programme (EGASP) indicate increasing resistance to cefixime, ceftriaxone and azithromycin in several countries, particularly in Asia.¹² In 2023, ceftriaxone resistance among isolates collected through EGASP sentinel surveillance was 20.4% (53/260) in Vietnam and 15.3% (42/274) in Cambodia.¹² A separate Hanoi study in 2023-2024 reported an even higher ceftriaxone-resistance estimate.¹⁷ These sentinel estimates are important warning signals but should not be interpreted as nationally representative prevalence estimates. They nevertheless indicate that ceftriaxone resistance may no longer be a rare or isolated phenomenon but rather an emerging regional threat with global implications.^12,17

More concerning is the increasing documentation of treatment failure. During the past decade, confirmed failure to cure gonorrhoea with ceftriaxone alone or combined with azithromycin has been reported in Australia, Austria, Canada, France, Japan, Slovenia, Sweden, the United States (US) and the United Kingdom (UK).^18-24 The first globally confirmed failure of dual therapy of ceftriaxone and azithromycin in the UK marked the pivotal moment, demonstrating that even last-line combination therapy may no longer guarantee cure.^25-26

These documented failures likely represent only a fraction of the true burden. Importantly, many of the best-characterized treatment failures and highest resistance estimates have been identified in settings with functioning culture, antimicrobial susceptibility testing, treatment-failure investigation and genomic surveillance. These capacities remain limited in most countries – particularly in LMICs.²⁷ The apparent geographic distribution of resistant gonorrhoea therefore partly reflects where surveillance is strongest; absence of detected resistance should not be interpreted as absence of resistance. The true global burden is likely underestimated.

Scientific innovation: from promising pipeline to new therapeutic options

Despite these concerns, there are compelling reasons for optimism. We are witnessing unprecedented innovation in STI prevention, diagnosis and treatment.

Nucleic acid amplification tests (NAATs) have revolutionized diagnosis by enabling accurate detection of urogenital and extragenital infections and facilitating self-sampling. Rapid point-of-care platforms can provide results within an hour.²⁸ Whole-genome sequencing has transformed understanding of transmission networks and resistance mechanisms.^13-14 Artificial intelligence (AI) and machine-learning approaches are being investigated as promising research tools to predict antimicrobial susceptibility and identify resistance patterns or hotspots; however, these approaches require further validation and are not yet established as routine clinical tools.²⁹ Resistance-guided diagnostics, particularly assays targeting gyr-A mutations, have introduced precision- medicine approaches that can restore selective use of ciprofloxacin and reduce dependence on ceftriaxone.³⁰

The therapeutic landscape has changed substantially. In December 2025, the U.S. Food and Drug Administration (FDA) approved two oral therapies for uncomplicated urogenital gonorrhoeae: zoliflodacin (Nuzolvence) and gepotidacin (Blujepa).³⁶ For the first time in more than three decades, novel antibiotics have entered the gonococcal treatment options. Zoliflodacin, a first-in-class spiropyrimidinetrione antibiotic, targets bacterial type II topoisomerase inhibitor through a novel mechanism of action. Its pivotal Phase III trials demonstrated non-inferiority to ceftriaxone plus azithromycin for uncomplicated urogenital gonorrhoeae, including activity against MDR strains.^31-32 Similarly, gepotidacin, another novel oral antibiotic targeting bacterial DNA replication enzymes, has demonstrated efficacy in phase III clinical trials.³³ These oral agents received FDA gonorrhoea indication for patients aged 12 years and older with limited or no alternative treatment options.³⁶ These approvals represent the first genuinely new oral therapeutic options classes for gonorrhoea in decades and expand treatment options at a critical point in the evolution of gonococcal AMR.

The history of N. gonorrhoeae has been a race between bacterial evolution and medical innovation. For decades, gonorrhoea has maintained the lead.

However, history provides an important warning: every previous antibiotic introduced against N. gonorrhoeae eventually lost effectiveness. New agents must therefore be introduced with robust antimicrobial stewardship, susceptibility and genomic surveillance, pharmacovigilance, treatment-failure monitoring and equitable access. Without these safeguards, resistance to these new therapies could emerge and spread rapidly.

Beyond antibiotics: the prevention opportunity

The most transformative opportunity may lie in vaccine development. Observational evidence that meningococcal outer-membrane-vesicle vaccines confer partial protection against gonorrhoea provides optimism that an effective gonococcal vaccine may be achievable.³⁴ Several gonococcal vaccine candidates are now in development, raising the prospect of long-term prevention rather than repeated cycles of antibiotic replacement.³⁵ Together with resistance-guided treatment, rapid diagnostics, and genomic surveillance, vaccination could shift the response from repeatedly reacting to resistance toward preventing infection and reducing antibiotic selection pressure.

Conclusion: a tipping point between failure and innovation

Whether scientific innovation can outpace bacterial evolution will determine the future of gonococcal AMR. The emergence of untreatable gonorrhoea is not inevitable. However, avoiding this outcome will require integrated surveillance systems, genomic epidemiology, antibiotic stewardship, equitable access to new diagnostics and treatments and sustained investment in research and vaccine development.

The global response must move beyond viewing gonorrhoea as merely another STI and instead recognize drug-resistant gonorrhoea as a global health security threat. Failure to act decisively risks allowing one of the most common bacterial infections to re-enter the pre-antibiotic era.

The next decade will likely determine whether gonorrhoea becomes a model of successful innovation against AMR or a cautionary tale of scientific progress that arrived too late.

The history of N. gonorrhoeae has been a race between bacterial evolution and medical innovation. For decades, gonorrhoea has maintained the lead. Recent advances in genomics, diagnostics, therapeutics and vaccine science suggest that medicine may finally be catching up. Whether these innovations are sufficient to change the course of gonococcal AMR will depend on the speed, at what scale, and with what stewardship and equity they are implemented.

The emergence of ceftriaxone resistance and increasing reports of treatment failure do not yet signify the arrival of untreatable gonorrhoea. They do, however, represent an unmistakable warning that the window of opportunity to act is narrowing. The next decade will likely determine whether gonorrhoea becomes a model of successful innovation against AMR or a cautionary tale of scientific progress that arrived too late.

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