Officials in the British government expect that a verdict on whether Pfizer Inc-backed COVID-19 vaccine works will be available before the results are in on AstraZeneca Plc's competing vaccine, it has been reported.
Britain believes that the vaccine, which Pfizer is co-developing with Germany's BioNTech SE, could be ready to distribute before Christmas, the Times said.
Pfizer's Chief Executive Albert Bourla has previously said the company could release data on whether or not the vaccine works as early as this month.
The U.S. drugmaker said this week if trials are successful the company expects to file for emergency authorization of the vaccine candidate from U.S. regulators shortly after it has enough safety data in late November.
Britain has agreed supply deals for six vaccine candidates including frontrunners from Pfizer and AstraZeneca.
However, the hopes of ending the Covid-19 pandemic with a vaccine were dealt a blow today as a senior British health chief warned the first approved jabs may not work.
Kate Bingham, head of the UK's Vaccine Taskforce, has already warned there is only a 'slim' chance scientists will have a jab before Christmas.
And now she has dampened hopes even further, warning that the first generation of vaccines — which are all still in human trials — are 'likely to be imperfect'.
In a commentary published in medical journal The Lancet, Ms Bingham said: 'We should be prepared they might not prevent infection but rather reduce symptoms, and, even then, might not work for everyone or for long.'
And she added 'we do not know that we will ever have a vaccine at all', cautioning that 'many, and possibly all' of the vaccines currently being investigated could fail.
Ms Bingham was appointed chair of the UK's Vaccine Taskforce for Covid-19 in May and reports directly to the Prime Minister on the progress of a coronavirus vaccine, which experts say is key to controlling the pandemic.
The taskforce, which Ms Bingham says was the 'brainchild of Sir Patrick Vallance' — Number 10's chief scientific adviser, is at the forefront of putting plans in place to get the UK population vaccinated.
'However, we do not know that we will ever have a vaccine at all. It is important to guard against complacency and over-optimism,' Ms Bingham said.
COVID-19 VACCINE 'MAY NOT PREVENT SEVERE ILLNESS OR DEATH'
Covid-19 vaccines may not prevent people from getting severely sick or dying, Professor Peter Doshi, the associate editor of the British Medical Journal, has warned.
Trials of hundreds of thousands of volunteers are investigating whether experimental Covid-19 jabs stop a person from picking up the infection.
But Professor Doshi commented in a piece published last week that scientists are not waiting to see whether volunteers are protected from severe disease or death if they do catch it — which would only be the case if the vaccine didn't work very well — before they are rolled out.
This is a particular concern for the elderly, who are the most at risk of severe Covid-19 outcomes, because the vaccine may not be as effective at protecting them from catching the coronavirus in the first place.
Vaccines typically do not work as well for those over the age of 60 because they have an aged immune system.
Professor Doshi, of the University of Maryland, also revealed that the studies will not prove transmission between people can be curbed. Scientists are not measuring if those who catch it pass it on to friends and family, regardless of whether they get sick themselves.
None of the front-runners — Moderna, Pfizer, AstraZeneca, Janssen, Sinopharm, or Sinovac — are measuring if their vaccines will save lives in their final stage trials.
Scientists wait for a number of people to catch the coronavirus so they can compare whether the infection rates are higher in those who received the experimental Covid-19 jab, or in the placebo group.
If cases are higher in the placebo group, it would suggest that the vaccine protects against catching the coronavirus, in theory.
None of the phase three trials are waiting for endpoints of severe disease or deaths before stopping the trial, which would confirm the vaccine is indeed 'life-saving'.
But in response to Professor Doshi's paper, scientists say there are 'excellent' reasons for running the trials, the main one being to speed up finding a vaccine which could otherwise take years because so few Covid-19 patients become severely ill.
Dr Andrew Preston, a reader in microbial pathogenesis who works in vaccines, University of Bath, told MailOnline: 'Covering every manifestation of Covid disease would require trials so large, that run for such long times, that they are very likely to be impossible to run and fund, and would delay the data so long that we’d be living without any vaccine-mediated intervention for years to come.'
Commenting on the BMJ editorial, Dr Preston argued there were 'excellent and sensible reasons for running the trials as they are'.
'To test vaccines in the very vulnerable would require vaccinating vulnerable people and then asking them to put themselves in situations in which they might be exposed to the virus.
'The ethics of this would be highly questionable, so it makes sense to test whether the vaccine shows any effect in people who, if they did become infected, the consequences are far less severe.'
However, he agreed that it is important for there to be clarity on what vaccine trials will and will not show.
Experts say it is highly unlikely that any vaccine approved for the coronavirus will ever completely proven to work before it is rolled out.
The World Health Organization admits 'no vaccine is 100 per cent effective'. For example, the measles jab, which has been doled out for decades, works 98 per cent of the time.
But if a jab prevents the large majority of people from catching the coronavirus, and potentially reduces the severity of the illness, then it will be hailed as game-changing.
The aims of coronavirus vaccine trials, which use tens of thousands of volunteers worldwide, is to see if the jab prevents SARS-CoV-2 infection.
But they will not reveal if the vaccines stop the chain of transmission, or prevent someone from getting severely sick or dying.
It would take several years to assess if a vaccine actually saves lives, which is why scientists have cut corners in order to develop one that at least reduces the risk of catching it.
Another obstacle in vaccinating the population is a lack of manufacturing capacity for the billions of doses required, Ms Bingham warned.
The Taskforce anticipates that most vaccines will require two doses to work, and possibly annual booster shots.
On top of that, 'the UK is committed to ensuring that everyone at risk of SARS-CoV-2 infection, anywhere in the world, has access to a safe and effective vaccine'.
Ms Bingham wrote: 'A major challenge is that the global manufacturing capacity for vaccines is vastly inadequate for the billions of doses that are needed, and the UK manufacturing capability to date has been equally scarce.
'There will not be one successful vaccine, or one single country, that is able to supply the world.
'We urgently need international cooperation to pool risks and costs, address barriers to access, and scale up the manufacturing capacity to produce sufficient doses to protect everyone at risk of SARS-CoV-2 infection globally.'
Ms Bingham revealed there are already 'deployment plans' for when a Covid-19 vaccine is ready because there will be huge logistical challenges in roll-out. These have been made for the NHS, GP surgeries, pharmacies, care home and pop-up sites.
She confirmed 'adults older than 50 years, health-care and social-care workers on the front line, and adults with underlying comorbidities' will be first in line.
A vaccine is considered key to ending the Covid-19 pandemic which has already killed 1.1million people worldwide.
It's not the first time Ms Bingham has attempted to dispel hopes of a Covid-19 vaccine ending the pandemic.
She said earlier this month that not everyone - potentially only half - of the British population would be vaccinated if a jab was proven effective against the coronavirus.
If any vaccine was proven to be 95 per cent effective, which is thought to be unlikely given the short time frame scientists have been working in, it may be given to a larger number of people.
Number 10 has already ordered 340million doses of seven different experimental jabs in a spread-betting approach that banks on one of them being proven to work.
Among them are three jabs created by Oxford University, Pfizer and Janssen – owner of Johnson & Johnson – which are all in the final stages of testing. But even if there was one ready by 2021, it would only be given to the most at-risk groups first, such as the elderly and NHS workers.
Ms Bingham said only vaccines that have the potential for approval by regulators and delivery as early as the end of 2020 or, at the latest, in the second half of 2021, have been considered.
One of the most advanced vaccines, developed by AstraZeneca and the University of Oxford, is tipped as the most likely to ready first.
Those created by Novavax - which Ms Bingham has received in trial - GSK and Sanofi, and Valneva 'will not be available until late in 2021', she said.
WHICH VACCINES HAVE THE UK SECURED DEALS FOR?
1. GlaxoSmithKline and Sanofi Pasteur: 60million doses
The Government revealed on July 29 it had signed a deal with pharmaceutical giants GlaxoSmithKline (GSK) and Sanofi Pasteur
If the vaccine proves successful, the UK could begin to vaccinate priority groups, such as frontline health and social care workers and those at increased risk from coronavirus, as early as the first half of next year, the Department for Business, Energy & Industrial Strategy (BEIS) said.
Human clinical studies of the vaccine will begin in September followed by a phase 3 study in December.
The vaccine is based on the existing technology used to produce Sanofi's seasonal flu vaccine. Genetic material from the surface protein of the SARS-CoV-2 virus is inserted into insect cells - the basis of Sanofi's influenza product - and then injected to provoke an immune response in a human patient.
2. AstraZeneca (manufacturing University of Oxford's): 100million
AstraZeneca, which is working in partnership with Oxford University, is already manufacturing the experimental vaccine after a deal was struck on May 17.
Professor Sarah Gilbert, who is leading the Oxford team, is confident the jab could be ready for the most vulnerable people by the end of the year.
Her comments came after the results from the first phase, published in The Lancet on July 20, showed promise.
The team have genetically engineered a virus to look like the coronavirus - to have the same spike proteins on the outside - but be unable to cause any infection inside a person. This virus, weakened by genetic engineering, is a type of virus called an adenovirus, the same as those which cause common colds, that has been taken from chimpanzees.
3. BioNTech/Pfizer: 30million
US drug giant Pfizer - most famous for making Viagra - and German firm BioNTech were revealed to have secured a deal with the UK Government on July 20.
It reported positive results from the ongoing phase 2/3 clinical trial of one called BNT162b1 on July 1. The company is still running phase 2 trials at the moment.
Pfizer's vaccine is one called an mRNA vaccine, which do not directly inject bits of the virus into the body but send genetic material.
mRNA vaccines programme the body to produce parts of the virus itself by injecting the body with a molecule that tells disease-fighting cells what to build. The immune system then learns how to fight it.
4. Valneva: 60million
The Government has given Valneva — whose vaccine is understood to be in the preclinical stages of development — an undisclosed amount of money to expand its factory in Livingston, Scotland.
While the Government revealed a 60million dose deal on July 20, the company said it had reached agreement in principle with the UK government to provide up to 100million doses.
Valneva's jab is an inactivated whole virus vaccine, meaning it injects a damaged version of the coronavirus itself into the body.
The virus has been destroyed in a way that makes it unable to cause infection, but the body still recognises it as a dangerous intruder and therefore mounts an immune response which it can remember in case of a real Covid-19 infection.
5. Janssen (Johnson & Johnson): 30million
The Government has agreed to buy 30million doses of a vaccine made by Janssen if it works.
Officials have agreed to help the company in its development of the jab by part-funding a global clinical trial. The first in-human trials of Janssen's jab began in mid-July and are being done on adults over the age of 18 in the US and Belgium.
The jab is named Ad26.COV2-S, recombinant, and is a type of jab called a viral vector recombinant vaccine.
Proteins that appear on the outside of the coronavirus are reproduced in a lab and then injected into the body to stimulate an immune reaction.
The 'Ad' part of the vaccine's name means it works using an adenovirus - a virus best known for causing the common cold - as a vehicle to transport the coronavirus genetics into the body.
6. Novavax: 60million
Britain has ordered 60million doses of a vaccine being developed by the US-based company Novavax. It will help to fund late-stage clinical trials in the UK and also boost plans to manufacture the vaccine in Britain.
Novavax's jab, named NVX-CoV2373, showed positive results in early clinical trials.
It produced an immune response in 100 per cent of people who received it, the company said, and was safe and 'generally well-tolerated'.
Novavax's candidate is also a recombinant vaccine and transports the spike proteins found on the outside of the coronavirus into the body in order to provoke the immune system.
7. Imperial College London: Unknown quantity
Imperial College London scientists are working on Britain's second home-grown hope for a jab. The candidate is slightly behind Oxford's vaccine in terms of its progress through clinical trials, but is still a major player.
The UK Government is understood to have agreed to buy the vaccine if it works but details of a deal have not yet been publicised.
Imperial's jab is currently in second-phase human trials after early tests showed it appeared to be safe.
Imperial College London will try to deliver genetic material (RNA) from the coronavirus which programs cells inside the patient's body to recreate the spike proteins. It will transport the RNA inside liquid droplets injected into the bloodstream.
No comments: