Fearful Brits fighting blood cancer have called for nearly quarter of a million people to be given their second Covid vaccine just three weeks after the first in order to save lives.
The government is under pressure to update its guidelines after worrying research suggested first doses may be ineffective for some patients.
People with conditions such as leukaemia have been devastated to find they had no coronavirus antibodies weeks after receiving their first jab - and told The Mirror rules need to change.
Charity Blood Cancer UK has called on ministers to consider giving second doses after three weeks to those at highest risk.
It comes after a study found that after one dose of the Pfizer vaccine, just 13 per cent of a small sample of blood cancer patients developed lifesaving antibodies.
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The research, by experts from King's College London and the Francis Crick Institute, found that an early second dose appeared to increase antibody response in 95 per cent of cancer patients.
With lockdown restrictions set to be eased further from next week, it has prompted warnings to the public not to be complacent - as some who have been vaccinated may not have protection against Covid.
Among those who found they do not have any antibodies weeks after being vaccinated is Stephen Pollard, who was diagnosed with leukaemia six years ago.
Stephen, who has been shielding throughout the pandemic, told the Mirror he took an antibody test eight weeks after being given his first dose of the Oxford/AstraZeneca vaccine, but was distraught when it came back negative.
The 56-year-old has called for second doses to be given faster to people battling blood cancer in the UK.
He said: "It seems slightly ridiculous that they aren't giving it a go when the evidence is showing it's not working for people who have had the first jab.
"It's not queue jumping, we're not taking anyone else's second dose.
"I completely support the 12 week gap for most people, it appears to be working. There's only 230,000 people affected by this, by comparison it's a tiny number.
"We're all in the same boat, people are angry as this feels like a bureaucratic decision."
Stephen, editor of the Jewish Chronicle newspaper, continued: "The consensus seems to be that one way to make sure that they don't work is to space out the vaccine.
"As it's been explained to me, its like trying to start a car if you keep at it. The second time it needs to have something to work with."
Mel Plumridge, 60, who is being treated for chronic lymphocytic leukaemia, warned the public need to be aware that not everyone classed as vulnerable is protected.
He said: "I think there's a lack of awareness that the vaccine isn't a silver bullet for everybody.
"People are saying 'I've had my vaccine, when can I go out?' But for 230,000 people and their families this isn't over and it's not going to be over for a long time."
Mel, from Crick in Northamptonshire, told The Mirror that he has had to try and keep his distance from his wife, a primary school teacher, throughout the crisis to reduce his risk.
He believes that speeding up second doses could make a difference, having received his first vaccine last month.
"For people with blood cancer, to get the second dose as close to three weeks as possible may give it the best chance of working," Mel said.
David Lauder, 63, who has chronic lymphocytic leukaemia, received his first vaccine eight weeks ago.
He said: "It's something we feel we can't control. One of the experts on a webinar I was on said there's some evidence for blood cancer patients to be vaccinated much closer to the first one.
"I'm not a scientific expert, but they seem to agree this would be a good idea."
He is due to have his second jab at the end of April, but said: "If we could have the second one sooner, it would be more reassuring."
Gemma Peters, chief executive of Blood Cancer UK, told the Mirror that the pandemic has had a devastating impact on patients, and the latest study has caused further worry.
She said: “People with blood cancer are at much higher risk of becoming seriously ill from the coronavirus and so have now been avoiding social contact for over a year, with the mental health toll that has come with this.
"Given this, the news that Covid vaccines may be less likely to be effective for them is very worrying of them, but the latest research suggests people with cancer may get more protection from having their two vaccinations closer together.
"The Government should let doctors make decisions about what’s best for their individual patients, both in terms of if they would benefit from getting the vaccine doses closer together and if vaccinating the adults they live with could help protect them.
“The Government also needs to do more to fund the research that could tell people with blood cancer whether the vaccines are likely to work for them. This research will mean those who are protected can start to get back to their normal lives, while those who aren’t can get the support they need to protect them from the virus.
"So far, the Government hasn’t provided enough money to do this properly, with the real risk that everyone with blood cancer could end up feeling they have to avoid social contact indefinitely.”
Julia Frater, a senior cancer information nurse from Cancer Research UK, said: "Last week we saw reports of an interesting study that was looking at early results of how effective the vaccine is in protecting cancer patients from COVID-19.
"However, it’s important to note that at this stage we are looking at data that hasn’t been peer-reviewed, where other experts in the field would flag errors and limitations within the results.
“The numbers of patients looked at in the study are also relatively small, particularly for those with blood cancers. We know that this information could be worrying, but anyone undergoing cancer treatment should continue to follow the advice of their doctors, and we encourage all who can to take up the vaccine.”
The Department of Health said that data is constantly being reviewed by the Joint Committee on Vaccination and Immunisation (JCVI).
A spokesman told The Mirror: “We are focused on saving lives and the antibody response is only part of the protection provided by the vaccine.
“The independent Joint Committee on Vaccination and Immunisation, which advises government on vaccine use and prioritisation, regularly reviews data and evidence on vaccine efficacy and effectiveness.
“Over 28 million people have now received their first COVID-19 vaccine dose and everyone in priority groups 1-4, including those who are clinically extremely vulnerable, have been offered their first jab.”
