By Bond Robertson 
Protein-based vaccines will soon become another weapon in the fight against COVID-19. Swedish researchers stress that these vaccines have been well tested against other infections.
Before Christmas, the European Medicines Agency (EMA) approved a new vaccine, Nuvaxovid from Novavax. According to the Norwegian Medicines Agency, its protective effect against serious illness and death is 90 percent.
Unlike other vaccines, this is a protein-based vaccine. It uses an older and more traditional technique used in hepatitis B vaccines, among other things.
The researchers hope that protein-based vaccines will be able to provide more long-term antibody protection, so more people will take the vaccine as well.
With mRNA technology, used in the Pfizer-Biontech and Moderna vaccines, massive amounts of doses can be produced quickly. It has saved millions of lives during the pandemic.
However, it has been shown that the antibodies that protect against infection decline relatively quickly, although protection against serious diseases is likely to last longer.
Protein-based vaccines are a type of vaccine we’ve used before and we know of any side effects. We also hope the protection will last a little longer compared to mRNA vaccines, or those based on vectors, as you see the effect decrease after six months, says Ali Mirazimi, professor and vaccine researcher at Karolinska Institutet.
Of course, he adds, you definitely don’t know this until you start vaccinating.
need excipients
mRNA technology introduces the mRNA molecule, which contains an “instruction model” for how the body itself produces the proteins it wants the immune system to respond to.
On the other hand, protein-based vaccines contain protein particles from the virus that are produced in a laboratory and injected with an excipient.
– Another substance that stimulates the immune system must be brought in, so that the body reacts with this protein, and it is called an adjuvant, says Mirazimi.
Common in vaccines, they stimulate the production of antibodies and memory cells, which train the immune system to recognize and stop the virus. Protein vaccines can have an advantage in that they usually give a higher level of antibodies and therefore a longer protective effect.
know very little
However, so far very little is known about the ability to decide which types of vaccines are best, stresses Karen Lowry, professor of immunology at Karolinska Institutet.
– She adds that there are many indications that protein-based vaccines provide very good levels of antibodies, but you have to wait a bit before you can say for sure that it will make a big difference compared to the mRNA vaccine.
Declining antibodies over time is common to all vaccines, but the higher the levels are from the start, the longer it takes before the levels become too low to have any effect. Lowry thinks that even with the protein vaccine, everything indicates that refills will be needed.
Many groups of patients
Both Lowry and Mirazime see many benefits of having different types of vaccines on the market.
People for various reasons may be afraid of the mRNA vaccine. Or they feel safer taking a protein-based vaccine because it’s already known — and you know they usually work very well, says Karen Lowry.
The two experts also noted that protein vaccines can be given to patients who, for various reasons, cannot take other vaccines.
Sometimes you may not be able to get a vaccine for various medical reasons. For example, some people have severe allergies and cannot take the mRNA vaccine. Therefore, the protein vaccine may work for some patient groups, Mirazimi says.
Can be stored in the refrigerator
Protein-based vaccines also have the great advantage that they can be stored at refrigerator temperature, which makes storage and distribution a lot easier.
According to Laurier, there is also data to suggest that protein-based vaccines tend to cause slightly fewer side effects, such as flu-like symptoms or arm pain. It has been discussed whether they may therefore be more suitable for children or the elderly in the future.
However, the only protein vaccine approved to date – from Novavax – is recommended for adults aged 18 and over.
A significant drawback is that protein vaccines take longer to mass-produce.
A protein vaccine update will take longer to work against new variants of the virus, says Karen Lowry.
It is unclear when protein-based vaccines might be widely used. Vaccine coordinator Richard Bergstrom says Sweden has already ordered 4.1 million doses of Novavax, but would be happy if Sweden received 100,000 during the first quarter of 2022.
The end of covid-19?
Karen Lowry thinks it may be a while before production reaches needed quantities, but she hopes the supply will eventually be so good that you can choose the vaccine yourself — or at least discuss your choice with your doctor.
She believes that protein-based vaccines may help eradicate the coronavirus.
Yes, like mRNA vaccines. If we continue to vaccinate diligently, the virus will eventually be eliminated. But I don’t think protein-based vaccines are the miracle. What’s important, Laurie says, is to vaccinate people.
Mirazimi believes that the virus will not disappear completely because it is a zoonosis, an infectious disease that can spread between animals and humans.
But what is absolutely clear is that we can reduce the spread of infection and the burden on the health care system. This fight requires both vaccines and antiviral drugs. He says protein-based vaccines can certainly contribute.