A first-of-its-kind trial has been launched to test a new vaccine for bird flu in humans, amid the “real possibility” of human-to-human transmission.
Thousands of people in the UK are expected to be recruited for the study, with poultry farmers or those who have close contact with birds encouraged to sign up.
Experts have warned that the A(H5N1) strain of the virus is evolving and spreading in animals, and while it does not yet move easily between people, society must be wary of the risks of human-to-human transmission developing.
Dr Rebecca Clark, who is based at Layton Medical Centre in Blackpool and is the trial’s national co-ordinating investigator, said: “We know that the A(H5N1) strain is evolving and spreading across animal species, and though it does not yet move easily between humans, we have to treat human-to-human transmission as a real possibility.
“This trial is our proactive attempt to shield against that possibility, and any future pandemic that could emerge from it.”
The mRNA-1018 vaccine, developed by Moderna, uses mRNA technology, similar to jabs for Covid-19.
It instructs the body to produce specific proteins from a specific virus to help train the immune system to recognise and respond quickly if it comes into contact with the illness.
The phase 3 trial will include around 4,000 people in the UK and the US.
Some 3,000 UK patients – half of whom will be over 65 – will have the jabs at 26 sites across England and Scotland.
The A(H5N1) strain has come to affect birds globally in recent years, but has also caused outbreaks among other animals such as mink and marine mammals.
It had also spread to dairy cows in the US, with several human cases in those working on farms with affected cattle.
The study, backed by the National Institute for Health and Care Research (NIHR) and sponsored by Moderna, will take seven months, with patients given two doses of the vaccine three weeks apart.
According to Dr Hiwot Hiruy, senior director of clinical development at Moderna, said early trials of the jab found it to be “generally well tolerated, with most of the side-effects being mild to moderate, and there were no safety concerns”.
She added: “We also saw that mRNA-1018 induced a strong immune response, and that we were able to pick that immune response as early as seven days after the first injection, and the immune response persisted.”
Given the absence of bird flu in humans, researchers will use the immune response as an early indicator that the treatment is likely to work.
The A(H5N1) bird flu viruses first emerged in southern China in 1996, with the first human infections recorded a year later.
Since 2024, there have been 116 confirmed cases of bird flu in people across the world, with almost all linked to close contact with infected animals.
Dr Richard Pebody, director of epidemic and emerging infections at the UK Health Security Agency (UKHSA), said: “We clearly don’t know when the next pandemic is going to be, we obviously don’t know what it’s going to be caused by, but what we do know is that a flu pandemic is the most likely future pandemic.”
He added that while the current risk of bird flu in humans “remains low” the virus “continues to evolve”.
“UKHSA remains alert to the potential that this pathogen could adapt to spread from person to person, and will continue to monitor all available data,” Dr Pebody said.
At the end of 2024, the government announced it had agreed a contract for more than five million doses of an H5 influenza vaccine to bolster pandemic preparedness.
The jab is based on a current H5 bird flu virus.
However, Dr Pebody said that the current stockpile uses more traditional vaccine technology.
Dr Hiruy also said that mRNA vaccines can be produced faster and can be adjusted to strains rapidly.
She said that while there are other vaccines out there, the new jab would be an “additional tool in pandemic preparedness””.
Follow STV News on WhatsApp
Scan the QR code on your mobile device for all the latest news from around the country
