[ad_1]
Five years minimum. That’s the time it usually takes to develop a vaccine. However, of the 78 that are being worked for Covid-19, five are already in tests, and not only in the laboratories; most are being tested on humans.
Last month, a microbiology researcher at Oxford University became the first UK volunteer to receive an experimental vaccine. The first in the world was a mother of two from Seattle in the USA. The US, which, on March 16, received a different experimental vaccine just 76 days after ‘unknown pneumonia’ was first reported to the World Health Organization on December 31 last year.
“The most urgent shared effort of our lives” is how Boris Johnson described the race to find a vaccine yesterday. And a career that certainly is.
Five years minimum. That’s the time it usually takes to develop a vaccine. However, of the 78 that are being worked for Covid-19, five are already in tests, and not only in the laboratories; most are being tested on humans (archive photo)
Typically, before a vaccine is released, years of research are done to see what kinds of immune-responsive pathogens, such as viruses or bacteria, are activated in the body.
After this, the type of vaccine is selected: some involve a weakened virus; Others may be based on toxins produced by a pathogen. But most contain what are called subunits: proteins or particles from the surface of the virus.
The vaccine must then undergo at least three phases of human testing, beginning with small studies to determine safety. Larger trials follow to find the correct dose and verify that the vaccine works better than a placebo. Then it must go through strict regulatory processes.
To put the speed of this vaccine race in perspective, nearly 50 years passed between the detection of protective antibodies in measles survivors and the development of a safe vaccine in 1963.
“I worked on a vaccine and it took more than ten years to develop, and that’s not unusual,” says Lawrence Young, a professor of molecular oncology at the University of Warwick, who helped develop the human papillomavirus (HPV) vaccine. which is now routinely administered. In schools.
“Developing a vaccine is complex, in part because it will be given to healthy people, so there is a lot of regulatory and safety testing to overcome.”
Professor Young says that some experts fear that because a Covid-19 vaccine must develop rapidly, the cuts could be cut.
“We understand the rush, but we must be careful not to circumvent important security stages,” he adds. ‘Everything must be closely monitored.
“It seems strange that we still don’t know what a protective immune response to coronavirus looks like in the human body, and yet we are already working on vaccines against it.”
The Regulatory Agency for Medicines and Health Care Products, which ensures that vaccines meet safety standards, says it is accelerating the trial review and approval process, but that safety is not compromised, stating: ‘Trials are being reviewed in accordance with our robust quality and safety requirements.’
Normally, the body fights a virus or bacteria with antibodies, memory proteins, so that when invaders reappear, the antibodies recognize them and tell the immune system to attack. A vaccine copies this.
Peter Openshaw, professor of experimental medicine at Imperial College London, is “optimistic” that a Covid-19 vaccine can be found, but warns: “Success should not be assumed.” With coronavirus, you really need to focus your protection on the lining of the lungs, and that’s not easy.
“Most of the vaccines considered are injected into the muscles, which will generate antibodies that travel through the body.”
Even if scientists create a successful vaccine, producing enough can be a logistical nightmare. “It is not as simple as getting a bigger bottle: all processes should work as well on a large scale as on a small scale,” says Andrew Easton, professor of virology at the University of Warwick.
In Britain there are two main contenders in the vaccine race: one team at Oxford University and the other at Imperial College London. Last month, the government handed over £ 42.3 million to each other for their trials.
With so much hope, how do they fit in?
OXFORD TEAM IN SEARCH OF THE HEALING
Who is leading it? Sarah Gilbert, 58, a professor of vaccination, who previously worked on vaccines for Middle East respiratory syndrome (MERS) and influenza.
What is it made of? Called ChAdOx1 nCoV-19, the vaccine contains an adenovirus, a type of virus that normally causes the common cold, of a chimpanzee, which has been genetically modified, making it impossible for it to grow in humans. Inside the virus is a genetic code for a key part of the Covid-19 structure: one of the protein spikes surrounding the coronavirus. The virus uses these protein spikes to bind and enter our healthy cells.
The hope is that the vaccine will make the body recognize and develop an immune response to the spike protein Covid-19, and develop antibodies to use if it finds something real later.
Microbiologist Elisa Granato, 32, is injected as part of human trials in the UK for a coronavirus vaccine at the University of Oxford
When will testing begin? Human testing began on April 23 and already “several hundred” volunteers have had the experimental jab.
The team hopes to vaccinate 510 people ages 18 to 55, most of whom work in health care. Half will have the new vaccine and half a puncture of meningitis (as a control).
If initial tests are successful, they will puncture 5,000 volunteers, including those over the age of 70 who tend to have a lower immune response to vaccines.
Professor Gilbert has said that once they reach 30 infections (in the control group), they will be able to tell if it is effective as they will compare it to the number of infections (if any) in the coronavirus group.
Will it be ready soon? Last week, the team said it could have “signals” about whether the vaccine works in June. Previously, members said the “best case scenario” was that they would know if the vaccine was effective or not for the fall.
How safe are they? Professor Gilbert has said that she believes her vaccine has an ’80 percent chance of success.’
Any advantage? Scientists have been able to move forward quickly as they build on past experience of working with coronaviruses (which cause colds).
Last week, there was an announcement that the Oxford unit was partnering with British pharmaceutical giant AstraZeneca to manufacture and distribute millions of doses of the vaccine if it succeeds.
Possible pitfalls? As with any of the contenders in this country, the blockade will make it difficult to assess how successful a vaccine is because fewer people are spreading the virus.
Professor Gilbert says they may have to continue their trials in other countries where more viruses are circulating in the community.
It is also a complex approach, says Professor Easton. “The virus needs to grow in a cell, and increasing it could be difficult because you need to grow the cells in a medium, and then you need to make sure that it retains its purity when you make the vaccine.”
THE IMPERIAL OFFER TO SAVE JAB
Who is leading it? Robin Shattock, 57, professor of mucosal infection and immunity, who has spent many years researching treatments for HIV.
What is it made of? This consists of genetic material from the coronavirus called RNA (made in the laboratory), which carries instructions to tell genes to make proteins. The RNA is covered in a fat to help prevent it from degrading as soon as it enters the body and to generate a better immune response.
This vaccine is injected into a muscle, and the RNA then signals the cells to make a protein that is found on the surface of the coronavirus. The hope is that this will provoke an immune response and the production of antibodies.
Principal investigator Dr. Paul McKay works in the laboratory space created exclusively to help create a Covid-19 vaccine at Imperial College London
When will testing begin? Animal testing began on February 10 and human trials will begin in the “summer,” the team said.
Will it be ready soon? Professor Shattock says that if “everything goes well, it will be available next year.” However, last week he said: “If social distancing and blocking really work, it will take us longer to determine if a vaccine works.”
How safe are they? The professor has only said this: “I think we are very sure that some vaccines will come and work.”
Any advantage? A simpler approach than Oxford’s, this is a ‘synthetic’ vaccine that does not contain live viruses. Professor Shattock says that it would be easy to increase production and that a liter of vaccine would give a million doses.
Possible pitfalls? ‘This approach [using RNA in a lipid] it has never been used successfully as a human vaccine, “says Professor Openshaw.
“In preclinical models it works well, but previously, when this type of vaccine is given to humans, it didn’t work.”
