Home https://server7.kproxy.com/servlet/redirect.srv/sruj/smyrwpoii/p2/ Business https://server7.kproxy.com/servlet/redirect.srv/sruj/smyrwpoii/p2/ Here’s how some of the leading coronavirus vaccines work

Here’s how some of the leading coronavirus vaccines work

If positive, the company plans to apply for an emergency authorization from the US Food and Drug Administration and make the vaccine available to the public.

Two vaccines are already authorized by the FDA and the European Union, and three are authorized in the United Kingdom. Here’s how some of the best coronavirus vaccines and vaccine candidates work.

Pfizer and its German-based partner BioNTech are using a new approach to making vaccines that use messenger RNA or mRNA.

This design was chosen for a pandemic vaccine years ago because it is one that lends itself to a rapid reversal. All that is needed is the genetic sequence of the virus causing the pandemic. Vaccine manufacturers don̵

7;t even need the virus itself – just the sequence.

In this case, BioNTech researchers used a small piece of genetic material encoding a piece of the thorn protein, the structure that adorns the surface of the coronavirus, giving it that thorny appearance.

Messenger RNA is a single strand of the genetic code that cells can “read” and use to make protein. In the case of this vaccine, the mRNA instructs the muscle cells in the arm to make the specific piece of the virus’s protein. Then the immune system sees it, recognizes it as foreign and is ready to attack when the actual infection occurs.

“RNA is like snapchat messages that leak. RNA vaccines do NOT become a permanent part of your body. They are temporary messages instructing cells to produce a viral protein temporarily,” said Shane Croty, a virologist at the Institute of Immunology in La Jolla. Twitter.

“25 different coronavirus proteins are needed to make a coronavirus, so there’s no worry that RNA is producing a virus.”

Pfizer's Covid-19 vaccine appears to work against mutation in new coronavirus strains, study finds

Clinical studies have shown that the Pfizer vaccine is 95% effective in preventing symptomatic infections. Pfizer is working to show that the vaccine can prevent all infections, including those that do not cause symptoms.

MRNA is very fragile, so it is wrapped in lipid nanoparticles – a coating of an oily substance that can melt at room temperature. Therefore, the Pfizer vaccine should be stored at ultra-cold temperatures of about minus 100 degrees F (minus 75 degrees C). This means that special equipment is needed to transport and store this vaccine.

The Pfizer vaccine won the FDA EUA in December and is available to millions in the United States and the United Kingdom. The US government has signed a contract to purchase 200 million doses of Pfizer’s coronavirus vaccine.

Side effects are rare and usually mild. These include fever and headache, although very few people have had allergic reactions to the vaccine. It is not clear what causes the allergic reaction and the Centers for Disease Control and Prevention of the FDA and the United States are investigating.


Moderna vaccine is also based on mRNA. “MRNA is like cell software,” Moderna said on her website.

And like the Pfizer / BioNTech vaccine, it encodes cells to produce a piece of the protein. It was a careful choice – the scientists had to take a piece of the virus that they thought would not mutate or change much over time. The virus uses spike protein to grab the cells it attacks, and the structure appears to remain stable for a generation after generating viral replication.

Like the Pfizer vaccine, the Moderna vaccine enters the muscle cells of the arm and possibly nearby cells of the immune system and instructs them to produce pieces of protein with spikes.

Clinical studies have shown that Moderna’s vaccine is 94% effective in preventing symptomatic infections, and the company says it has data showing that the vaccine also prevents all infections, including those that do not cause symptoms.

Moderna believes her vaccine will protect against coronavirus for at least a year

Moderna came up with a different formulation for lipid nanoparticles to protect mRNA in its vaccine. These formulations are corporate secrets, but Moderna believes her approach is better and said her vaccine can be delivered at minus 20 degrees C (minus 4 degrees F) and can be kept stable for 30 days at 2 degrees up to 8 degrees C (36 to 46F)), the temperature of a standard home refrigerator.

The FDA approved the Moderna vaccine in December, and the United States contracted 200 million doses of Moderna vaccine.

Johnson & Johnson’s Vaccine Shoulder Janssen Pharmaceuticals

The Jansen coronavirus vaccine is a recombinant vector vaccine. It uses a genetically engineered version of adenovirus 26, which can cause the common cold, but has been disabled by genetic engineering. It also provides genetic instructions for making a piece of thorn protein.

This is a vaccine that has been tested on the market before. The vector adenovirus 26 was used to make the company’s Ebola vaccine, which won marketing authorization from the European Commission in July.

Johnson & Johnson coronavirus vaccine generates immune response, few side effects, in early studies

This is a single vaccine. Data from a phase 1-2 trial published in the New England Journal of Medicine this week showed that the vaccine generated an antibody response in volunteers aged 18 to 55 years, as well as a second batch of volunteers aged 65 and over. The side effects are minimal.

The company is also testing a two-dose regimen in volunteers to see if adding a second dose provides better protection or longer-lasting protection.


The AstraZeneca vaccine, made with a team from the British University of Oxford, is called a vector vaccine. It uses a common cold virus called adenovirus to transfer the protein protein from the coronavirus into cells.

It also aims to get people to make their own vaccines by throwing away small copies of protein, but the method of delivery is different. This adenovirus infects chimpanzees but does not infect humans. It is modified so that it does not reproduce – then genetically engineered to inject cells with DNA encoding the full protein of the coronavirus peak.

The Covid-19 vaccine may not be safe and other myths
This is a cheaper way to make vaccines – but slower than using RNA. The company is committed to making its vaccine affordable to countries around the world. The vaccine can be kept stable for six months at standard temperatures in the refrigerator, the company said.

It has been approved in the UK, but the US FDA is awaiting data from US trials. Confusing experimental data show that the AstraZeneca vaccine may be 70% effective on average.


The Maryland-based biotechnology company Novavax specializes in “protein subunit” vaccines. They use virus-like nanoparticles as a base and coat them with genetically engineered pieces of the coronavirus peak protein.

This is also a tried and true vaccine approach. The hepatitis B vaccine given to newborns is a protein subunit vaccine, as is the human papillomavirus or the HPV and FluBlok vaccine, Sanofi’s flu vaccine.

Novavax uses an insect virus called baculovirus to inject the coronavirus protein into the moth cells, which then produce the protein. This is collected and mixed with an adjuvant – an immunostimulant – based on saponin, found in trees from soap bark.

Sanofi and GlaxoSmithKline

It is also a protein subunit vaccine using Sanofi’s FluBlok technology with GlaxoSmithKline adjuvant. It also uses baculovirus to grow small pieces of protein.

Phase 1/2 studies show that the vaccine elicits an immune response comparable to patients who recovered from Covid-19 in younger adults, but the vaccine does not elicit the desired immune response in adult adults. The companies plan to launch a new trial in February.

Sinovac and Sinopharm

CoronaVac of the Chinese company Sinovac uses an inactivated virus – one of the oldest methods of vaccinating people. Whole batches of coronavirus are grown, “killed” and then vaccinated. Similarly, the Sinopharm vaccine in inactivated virus.

Sputnik V

The Russian coronavirus vaccine Sputnik V is an adenovirus vector vaccine. It uses two common cold viruses, called adenovirus 5 and adenovirus 26, to carry the genetic material for the thorn protein into the body.

Source link