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Coronavirus vaccine taken by tablet instead of injection is about to go into human trials

Millions of doses of a new Covid-19 vaccine could be in production by the end of the year, according to a San Francisco-based scientist who has been praised by Dr. Anthony Fauci for his work in the past.

Immunologist Dr. Sean Tucker is currently trialing several different vaccine candidates at his California lab – some of which will enter human trials at the start of July, and all of which are delivered by tablet rather than injection.

Speaking exclusively to DailyMail.com, Tucker said: ‘My hope is that us and others will be able to have very large vats of [vaccine] material, millions and millions of doses by the end of the year, early next year.

‘I mean, to me that doesn’t seem unreasonable given the amount of money the US Government and others have provided.

‘We hope that a vaccine solution will allow things to open up and for people to be going out and about again.’

Immunologist Dr. Sean Tucker (pictured) is currently trialing several different Covid-19 vaccine candidates at his California lab – some of which will enter human trials at the start of July, and all of which are delivered by tablet rather than injection

The vaccines are made from a dead adenovirus, one of the causes of common colds - and Tucker's team inserted some of the genes that make up Covid-19. Along with his eight-strong team, he has been working seven days a week since January in a bid to come up with a viable vaccination

The vaccines are made from a dead adenovirus, one of the causes of common colds – and Tucker’s team inserted some of the genes that make up Covid-19. Along with his eight-strong team, he has been working seven days a week since January in a bid to come up with a viable vaccination 

HOW THE TABLET VACCINE WORKS 

Tucker’s vaccine candidates work by delivering selected Covid-19 genes encased in a dead adenovirus to the lower intestine.

The adenovirus has been genetically modified to ensure it survives exposure to stomach acid and doesn’t open up until it reaches the small intestine.

Once there, it is designed to react with mucosa in the intestine and provoke an immune response to the Covid-19 genes.

The IgM and IgG antibodies it creates then circulate in the blood and have been taught to attack anything that looks like Covid-19 trying to attach itself to a wet surface such as the lungs.

According to Tucker, the advantage of a tablet vaccine, as opposed to the traditional jab, is that the body isn’t trained to attack the vector – the adenovirus – because a tablet doesn’t physically damage the body, unlike a jab which leaves a small wound.

Because of the wound, an immune response to the vector is sometimes also created which means the vaccine can only be used once.

By contrast, a tablet can be used as a booster as well as an initial vaccine. 

Tucker, 52, is the chief scientific officer at Vaxart – a publicly listed biotech company that specializes in the development of oral recombinant vaccines.

Along with his eight-strong team, he has been working seven days a week since January in a bid to come up with a viable vaccination for Covid-19.

He currently has several contenders, all of which are being fast-tracked through trials.

The vaccines are made from a dead adenovirus – one of the causes of common colds – into which Tucker’s team have inserted some of the 30 genes that make up Covid-19’s DNA.

Adenoviruses are extremely common and behind approximately 10 percent of childhood illnesses and almost every child has had at least one illness caused by adenoviruses by the time they reach 10.

Tucker explained: ‘We essentially build in DNA that encodes proteins of Covid-19. If you put it in the intestine in the right context, you get a really strong immune response to those proteins.

‘Because we’re delivering it to a wet surface – the mucosa of the intestine – you get a great immune response throughout the blood but you also get antibodies and T cells at sites of the infection in the lungs.

‘That’s the way our vaccine works – it’s designed to mount an immune response on wet surfaces such as the respiratory tract, which Covid-19 infects.’

Tucker’s process begins with making the adenovirus in the lab and then attaching a bioengineered molecule that tweaks it and allows it to pass through the stomach and work in the intestine. 

Covid-19 genes are then inserted into the virus. Not all are used, just those that appear likely to produce a strong immune response.

The vaccines are currently being lab tested for suitability for manufacture and simultaneously trialed on mice – and Tucker says the results have been promising so far.

Earlier this month, Vaxart announced the animal trials had shown an unusually early Immunoglobin G [IgG] response to Covid-19.

Unlike most vaccines, which are made to be injected, Tucker's drug will be delivered in tablet form which, he says, is more quickly manufactured and gets around the current global shortage of vials and syringes caused by the pandemic

Unlike most vaccines, which are made to be injected, Tucker’s drug will be delivered in tablet form which, he says, is more quickly manufactured and gets around the current global shortage of vials and syringes caused by the pandemic

IgG is an antibody that kills off viruses after they have been identified via an initial Immunoglobin M [IgM] response.

Once the attacker has been identified by IgM antibodies, the body produces IgG to kill the new virus off.

Those antibodies then remain in the blood and will attack anything that looks similar.

People who have already had Covid-19 already have coronavirus-killing igG antibodies and it is those that appear in antibody tests for the virus.

In July, phase one human trials will begin using a small group of patients. The trials will check whether the vaccines work and whether they produce any side effects.

If all goes well, the drug will move into phase two, which uses a larger test group, followed by phase three which involves hundreds of people and would usually compare the drug to a standard product already available.

The final phase focuses on whether the vaccine produces any long-term benefits or harms.

Volunteers will be recruited via research groups, many of whom use social media to approach test subjects who can be based anywhere in the US.

Previous Vaxart human trials have been conducted in all parts of the country: Costa Mesa, California, Kansas City, Missouri, and Cleveland, Ohio.

Unlike most vaccines, which are made to be injected, Tucker’s drug will be delivered in tablet form which, he says, is more quickly manufactured and gets around the current global shortage of vials and syringes caused by the pandemic.

The last vaccine Tucker worked on was a tablet-based flu inoculation, a joint project between Vaxart and Stanford University, which began in 2015 and completed trials in January. A study published in medical journal The Lancet showed it was just as effective as a regular flu shot and the development was hailed by Fauci who described it as 'encouraging' and 'potentially important'

The last vaccine Tucker worked on was a tablet-based flu inoculation, a joint project between Vaxart and Stanford University, which began in 2015 and completed trials in January. A study published in medical journal The Lancet showed it was just as effective as a regular flu shot and the development was hailed by Fauci who described it as ‘encouraging’ and ‘potentially important’

Tucker's process begins with making the adenovirus in the lab and then attaching a bioengineered molecule that tweaks it and allows it to pass through the stomach and work in the intestine. Covid-19 genes are then inserted into the virus. Not all are used, just those that appear likely to produce a strong immune response

Tucker’s process begins with making the adenovirus in the lab and then attaching a bioengineered molecule that tweaks it and allows it to pass through the stomach and work in the intestine. Covid-19 genes are then inserted into the virus. Not all are used, just those that appear likely to produce a strong immune response

But whatever the delivery method, the pressure to create a vaccine is enormous.

Currently, there are 120 projects worldwide focused on developing a vaccine for Covid-19, five of which have already moved into human trials.

One is in Seattle, Washington, where pharmaceutical company Moderna has begun phase one of a clinical trial on humans, using 45 healthy volunteers.

Elsewhere, a team at the University of Oxford in the UK began a trial using 500 volunteers in late April, while Pfizer teamed up with a German company for a trial that started early this month involving another 200 people in the US.

Ordinarily, creating a vaccine takes around four years and is then followed by an approval process that can take up to 18 months.

The last vaccine Tucker worked on was a tablet-based flu inoculation, a joint project between Vaxart and Stanford University, which began in 2015 and completed trials in January.

A study published in medical journal The Lancet showed it was just as effective as a regular flu shot and the development was hailed by Fauci who described it as ‘encouraging’ and ‘potentially important’.

Speaking to Fox News after that vaccine was announced, Fauci said: ‘The results from the challenge study are encouraging.

‘It will be important to determine how the vaccine performs with natural infection in the community.’

Tucker admits it's a gamble saying there's a chance none of the candidates could be the right one but says the results of the animal trials have been promising. For Tucker, the swift production of IgG antibodies at an early stage is a promising sign that not only does his candidate vaccine work, it works fast

Tucker admits it’s a gamble saying there’s a chance none of the candidates could be the right one but says the results of the animal trials have been promising. For Tucker, the swift production of IgG antibodies at an early stage is a promising sign that not only does his candidate vaccine work, it works fast

Vaxart say the flu tablet will go into production ‘very soon’ and doses will be available in the second half of 2020, assuming it passes an FDA review.

This time, things are different with Tucker and his team running tests simultaneously in order to fast track the process.

As with the H1N2 – or swine flu – epidemic in 2009, the hope is to formulate a vaccine as swiftly as possible. On that occasion, a jab was created and approved in just five months.

Tucker says the process is being sped up by increased communication among scientists and a greater willingness to pool information.

One of his regular calls is to Dr Sarah Gilbert, the Oxford University vaccinologist leading the UK’s best-known vaccine trial, but he says the key piece of information so far has been the release of Covid-19’s DNA by Chinese scientists early on.

He said: ‘There’s a lot more collaboration right now. When I talk to people on the phone, people are sharing information.

‘There’s a lot more provided before publication so there’s a lot more information out there and that’s been great.

‘Obviously, when Covid came out, Chinese investigators shared the sequences as early as they could so people could get on it and start making vaccines and I think that was important.’

The vaccines are currently being lab tested for suitability for manufacture and simultaneously trialed on mice – and Tucker says the results have been promising so far

The vaccines are currently being lab tested for suitability for manufacture and simultaneously trialed on mice – and Tucker says the results have been promising so far

Tucker added: ‘We started at the end of January. At that point in time, everybody was still like is this a real pandemic or is it not? By the middle of February, we knew this thing was going to be a big problem so we started working really hard.

‘As soon as we got the sequences [for Covid-19], we called up on the phone and ordered the DNA to be gazetted into our system and it arrived about mid-February.’

Since then, the team have developed several candidate vaccines using previous coronavirus research to make assumptions about what sort of immune reactions would tackle it best.

Tucker admits it’s a gamble saying there’s a chance none of the candidates could be the right one but says the results of the animal trials have been promising.

He told DailyMail.com: ‘We are getting really nice strong immune responses really early. We’ve publicly announced that we’re making a very strong IgG antibody response at very early time points and that is unusual.’

For Tucker, the swift production of IgG antibodies at an early stage is a promising sign that not only does his candidate vaccine work, it works fast.

He said: ‘We’ve been trying to understand all of the different [candidate vaccines] we have going forward and working out which one works best.

‘Everything so far is looking good at early time points. I think the data suggests we’re going to have a really nice solution.’

Read more at DailyMail.co.uk


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