The gap between the first and second dose of coronavirus vaccines could extend beyond the 12-week goal, health heads said today.
When the Pfizer Covid shot was approved, it was on the condition that people would receive a second dose three weeks after their first dose, as was done in clinical studies.
But UK regulators claimed there was enough data to prove it could be extended to three months, allowing No10 to give its first doses to twice as many people before larger deliveries of the injections arrive in the spring. Pfizer hit back, saying there was no evidence that the vaccine worked when the two doses were given so far apart.
Now older people who have already had their first injections may experience even longer and potentially open gaps between the two doses.
The Joint Committee for Vaccination and Vaccination has approved the second injection, which may be given 21 days after the first injection, without an upper limit.
And Public Health England’s chief of immunization, Dr. Mary Ramsey, said today, “It may very well be that we can afford to be more relaxed.” But regulators will only allow the gap to widen even if data shows first-dose protection lasts longer than expected.
Speaking at a meeting with MPs from the Science and Technology Committee, Dr. Ramsay said it was possible that the priority in the spring could be to give jabs to younger people instead of giving older people a second dose.
It comes as England’s deputy chief of medical service, Professor Jonathan Van-Tam, said today that the country is in a ‘limited supply situation’ but assured that the public second doses had not been canceled.
Dr. Wei Shen Lim of the JCVI said the Pfizer vaccine seemed good enough after one dose that that could eventually become the norm, but it wasn’t official advice just yet.
Britain is struggling to use up all its stockpiles of vaccines to get the first doses to as many people as possible, and has successfully vaccinated 2.43 million people to date.
Dr. Mary Ramsay, of Public Health England (left), and Dr. JCVI’s Wei Shen Lim (right) said today that it is possible that people’s second dose of Covid vaccine could be extended beyond the 12-week limit set by the government.
Vaccines are now being offered to humans dose by dose to overcome a slow start to supply, and second doses will be provided from the spring when more injections are available and the outbreak has calmed down (photo: man gets vaccinated in Stevenage , Hertfordshire)
Speaking of second doses, Dr. Ramsay to the committee: ‘I now understand that people are rostered around the 12-week kind …
“The information they are getting now is that you will be vaccinated between three and 12 weeks after the first dose, so it does not promise them the vaccine after three to four weeks.”
She added: ‘The current advice from the JCVI is that they go back and do the second dose for the first group, so I expect this to be done in parallel, that we continue to roll out the following groups at the same time and that is an operational consideration for NHS England …
The JCVI currently says the second dose should be given no later than 12 weeks.
“ If we have additional data, the balance may just be in favor of more first doses again, so the situation may change as science changes. This is a very fast moving field. ‘
Dr. Ramsay said that, depending on what the data shows about the levels of protection from a single dose of the vaccine, officials may be “ more relaxed ” about giving second shots.
WORLD HEALTH ORGANIZATION REFUSED TO GOOD A 12 WEEK GAP BECAUSE THERE IS NO PROOF
The World Health Organization has declined to give its blessing to the UK’s plan to delay two doses of Pfizer’s coronavirus vaccine by more than a month.
UK officials decided to use all available doses of the Pfizer / BioNTech shot, which was first approved, to get a single dose to as many people as possible. During the process, they make people wait up to 12 weeks for their second shot.
Covid cases started to decline about 12 days after people got their first dose in studies, but because everyone got a second injection just 10 days later, scientists don’t know how long the immunity would last from the first shot.
The WHO said last week that governments should give people their second dose within 21 to 28 days of receiving the first, to ensure the vaccine works in the long term.
But it did not challenge the UK’s decision not to do so, admitting that the government was forced to make a tough decision due to increasing infections and deaths in recent weeks.
One of the experts said they “fully recognize that countries may need to be even more flexible in terms of second dose administration.”
In a meeting to discuss how the doses are distributed yesterday, WHO experts concluded that people with the Pfizer / BioNTech shot should receive their second dose 21 to 28 days after the first, with an ‘outer limit’ of six weeks.
This maximum limit is only half as long as the UK plans to leave, and hundreds of thousands of people are being told they may have to wait three months.
Professor Jonathan Van-Tam, Deputy Chief of Medical Service for England
When asked if this could mean that people have to wait longer than 12 weeks, Dr. Ramsay added: “I think that’s unlikely, but it’s always possible – as you know in the Covid situation, everything will change when new evidence comes.”
The choice to extend the second dose period to more than three weeks caused controversy among scientists and doctors when it was announced because it had not been tested in clinical trials.
In the Pfizer and BioNTech studies, everyone who received the vaccine got a second shot about three weeks after the first, and the results showing how effective it is are all based on this.
While data showed that protection started about two weeks after the first dose, with Covid cases in the group slowing down from that point, scientists cannot say how long this single-dose protection would last.
But the JCVI has said it is satisfied that there is enough evidence that a high level of immunity would persist after the first dose.
Dr. Wei Shen Lim said the data may even be strong enough to move to a single-dose schedule in the future.
He told MPs this morning: ‘We noticed that the vaccine had a very high level of protection after the first dose.
‘And we had also considered whether the first dose provided sufficient protection, so that people could eventually consider using a single dose.
‘But we felt that then too [before Christmas] there were insufficient data to suggest a single dose regimen.
Even now, the JCVI’s advice is that the schedule is a two-dose schedule, which has not changed – we insist a two-dose schedule is the correct schedule – the difference is that we’ve been more tolerant of when the second dose can be given. ‘
He reiterated the JCVI’s advice that the second dose of Pfizer be given between three and 12 weeks and the second dose of Oxford between four and fourteen weeks.
Dr Lim added: ‘The EMA [European Medicines Agency] approval is that the second dose can be given at a minimum of 21 days, with no upper limit to that regulation.
The MHRA followed suit and changed their regulatory approval so that the second dose of the Pfizer vaccine can be given from 21 days with no upper limit. So that even more flexibility is possible. ‘
Their comments as Deputy Medical Officer Professor Jonathan Van-Tam said the UK is in a ‘supply constrained situation’.
There is some confusion as to whether companies making the vaccines are delaying the program by not producing fast enough, or whether the NHS’s network is not working fast enough to deliver the doses it has.
Professor Van-Tam said it was up to the manufacturers, who in turn said they are being delayed by rigorous quality controls before they can be used.
Professor Van-Tam said to LBC Radio today: “I understand the concerns people are having about this, but I want to make it clear that the second dose will not be canceled, but will be delayed.
‘We will definitely come back to the second dose and it is very important to come back to it.
‘But if we go from the outside in, we find ourselves in a limited supply situation.’