Doctors have started testing the world’s first mRNA vaccine against norovirus, a virus that causes severe vomiting and diarrhea. The hope is that the vaccine will provide significant health and economic benefits. Norovirus spreads easily, especially in places where people are in close contact, such as hospitals, schools, care homes, and nurseries. Though most people recover in two to three days, the virus can be serious for the elderly, very young, or those with weakened immune systems.
Currently, there are no approved vaccines for norovirus, and people who become seriously ill are treated with intravenous fluids. Dr. Patrick Moore, a GP and national chief investigator for the UK trial, explained that norovirus has a substantial global impact, with approximately 685 million cases and 200,000 deaths each year. In the UK alone, there are about 4 million cases annually, leading to 12,000 hospitalizations in England. Norovirus also places a heavy economic burden on the healthcare system, costing the NHS around £100 million annually, with an additional £300 million lost in earnings due to illness.
We wouldn’t be doing this sort of trial at this sort of pace if it wasn’t going to benefit the individuals themselves
Professor Saul Faust University of Southampton.
The new vaccine trial, called Nova 301, is a phase 3 clinical study that will run for two years and enroll 25,000 adults, particularly focusing on individuals over 60. Participants will be recruited from multiple countries, including Japan, Canada, and Australia. In the UK, the trial will take place at 27 NHS sites across England, Scotland, and Wales, with around 2,500 participants. To make participation easier, mobile units will be employed to reach a wider group of volunteers.
This trial is part of a 10-year partnership between Moderna and the UK, known as the Moderna-UK Strategic Partnership. It involves collaboration with the National Institute for Health and Care Research (NIHR), the Department of Health and Social Care (DHSC), the UK Health Security Agency (UKHSA), and Moderna, which is producing the vaccine.
Participants in the trial will be randomly assigned to one of two groups: half will receive the new mRNA vaccine, while the other half will receive a placebo saline shot. The vaccine uses mRNA technology, similar to the approach used by Moderna and Pfizer/BioNTech in their COVID-19 vaccines. The mRNA in the norovirus vaccine provides human cells with instructions to create proteins associated with the virus. These proteins, in turn, trigger the immune system to generate protection against future norovirus infections.
In this case, the mRNA in the vaccine instructs cells to produce the protein coat for three different types of norovirus. These harmless virus-like particles prompt the immune system to produce antibodies, which should protect against future infections.
Earlier trials of the vaccine showed that it successfully generated a strong immune response in humans. The current phase 3 trial will assess the vaccine’s effectiveness against the virus itself and determine how long the protection lasts. Dr. Doran Fink from Moderna mentioned that an efficacy rate of at least 65% or higher would be considered a meaningful result.
If the trial proves successful, Moderna plans to submit a marketing application to regulators in 2026, with the review process taking up to a year. Additional trials would also be conducted in teenagers and younger children.
At least 65% [efficacy] or higher is what we would consider to be clinically meaningful,
Dr. Doran Fink from Moderna
Professor Saul Faust, from the University of Southampton and co-clinical lead of the NIHR Vaccination Innovation Pathway, noted that a successful vaccine could have significant benefits for care homes, allowing them to operate as normal and enabling visits from loved ones without fear of norovirus outbreaks. Dr. Moore added that the vaccine could help prevent vulnerable individuals from becoming more frail due to the virus.
Faust emphasized the importance of the trial, saying, “We wouldn’t be doing this sort of trial at this sort of pace if it wasn’t going to benefit the individuals themselves.”
The vaccine is expected to significantly reduce the burden of norovirus, both in terms of health impacts and the economic costs associated with outbreaks. If successful, it would mark a major milestone in the fight against this highly contagious virus.
This article was later corrected on October 23, 2024, to clarify that while this is the world’s first mRNA vaccine for norovirus, it is not the first norovirus vaccine of any kind, as previously suggested due to an editing mistake.
Reference:
1. https://www.theguardian.com/society/2024/oct/23/doctors-trial-worlds-first-vaccine-against-vomiting-bug-norovirus
(Input from various sources)
(Rehash/Yash Kamble/MSM)
