In June 2023 GSK announced that the US FDA has granted fast track designation for its Neisseria gonorrhoeae investigational vaccine (NgG). This is intended to encourage the development and accelerate the review of important drugs and vaccines for conditions with unmet medical needs. The vaccine candidate is in an ongoing Phase II trial to assess the efficacy in healthy adults between the ages of 18 and 50 who are at risk of gonorrhoea.
The burden of gonorrhoea
As the second most prevalent bacterial sexually transmitted infection (STI) worldwide, it causes an estimated 82 million new cases each year. The CDC suggests that between 2009 and 2021 rates of reported cases increased by 118%. Gonorrhoea is caused by the bacterium Neisseria gonorrhoeae and is recognised as an urgent unmet medical need. Alongside growing incidence, drug-resistant strains are increasing.
When untreated, infection can lead to complications or long-term consequences such as pelvic inflammatory disease, infertility, ectopic pregnancy, or adverse pregnancy outcomes. It is more likely to be diagnosed in men than women due to symptom presentation, but due to stigma people are often hesitant to seek diagnosis or treatment. WHO states that most cases occur in the WHO African Region and the Western Pacific Region.
Increasing rates and AMR
Dr Phil Dormitzer, GSK’s Global Head of Vaccines R&D said that the team welcomes the decision to fast track the candidate.
“With a high and growing incidence, gonorrhoea is a major concern for sexual and reproductive health around the globe.”
The designation “recognises the potential for a vaccine” to protect people against the “serious health consequences of infection”. In addition to increasing rates of infection, antimicrobial resistance (AMR) to gonorrhoea has increased. This means that we are left with fewer treatment options. As there are no approved gonorrhoea vaccines, this candidate could help to tackle AMR by preventing infections. WHO warns of increasing prevalence of so-called “gonorrhoea superbugs or super gonorrhoea”.
The current trial
GSK’s trial is a Phase I/II trial to evaluate the vaccine candidate’s safety and efficacy. Phase I was a first-in-human dose-escalation safety lead-in conducted in health adults. The second phase is intended to demonstrate proof-of-concept. Across 8 countries around 750 subjects will be enrolled.