A UK company has started trialling a new universal influenza vaccine that would avoid the annual scramble to guess the most likely strains to be circulating in the following flu season.
The vaccine – developed by University of Oxford spin-out Vaccitech – will be tested in around 500 National Health Service (NHS) patients in a study supported by the National Institute for Health Research (NIHR). It is thought to be the first trial of such a vaccine and will extend over the 2017-18 and 2018-19 flu seasons.
The need for a more effective flu vaccine was starkly revealed last winter. The recommended vaccine was around 40% effective overall, but hardly provided protection at all to the over-65s who are most at risk of severe complications and death from the infection, despite being a good match for circulating strains of the virus.
The NIHR notes that flu affects about a billion people worldwide a year with 250,000 to 500,000 annual deaths, mainly in the over-65 age group. About 10,000 over 65s registered at six GP practices will be asked to take part in the trial in Berkshire and Oxfordshire this winter.
The new vaccine is designed to offer greater protection against flu because it targets the core proteins of the virus, which stay constant, while current vaccines target surface proteins (haemagglutinin and neuraminidase) that are constantly changing.
The World Health organization (WHO) delivers a recommendation each year on the strains of the virus most likely to be circulating in the northern and southern hemispheres, and vaccine producers then rush to get the shots available in time for the winter flu season in each region. Most of the time the predictions are good, but sometimes they miss the mark and a new strain emerges and becomes dominant, rendering the vaccination less effective.
A universal vaccine would sidestep that requirement, and potentially could also provide protection against emerging ‘pandemic’ strains of flu – for example crossing over from other species like pigs or birds – that it is feared could have a devastating impact on human populations.
Vaccitech’s vaccine is directed against influenza A, which is most likely to cause serious illness in humans and could provide five years of immunity from a single course, rather than requiring a new shot every year. That is because it stimulates the immune system to boost influenza-specific T-cells instead of antibodies.
The NHS is braced for a bad flu season this winter, following the worst outbreak in many years in Australia and New Zealand, according to a BBC report.