Vaccine Against COVID-19. How Optimistic Should Our Expectations Be?

Vaccine against COVID-19. How optimistic should our expectations be?

On Monday, March 16, the first clinical trial of a potential vaccine against the new coronavirus infection COVID-19 started in the United States. Its final results will be announced next summer. Think back to what we know about mRNA vaccines and the dangers of researching vaccines in humans without prior animal testing.

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On Monday, March 16, the first clinical trial of a potential vaccine against the new coronavirus infection COVID-19 started in the United States. Its final results will be announced next summer.

The vaccine is currently undergoing a phase I clinical trial. Its main goal is to make sure that the vaccine is safe by giving healthy people different doses. Scientists will conduct laboratory studies of participants' immunity indicators. But even if they turn out to be promising (for example, the concentration of antibodies will be high), this still does not mean that the vaccine will protect against the virus in real life. This will have to be confirmed by further testing.

An experimental vaccine mRNA-1273 refers to mRNA vaccines. It contains a fragment of mRNA that encodes an S-protein that helps the virus to attach to the cell. It is assumed that if a person receives a dose of the mRNA-1273 vaccine, his cells will produce some S-protein, and then the immune system will learn to recognize and destroy it. This will prepare the human body to fight the new coronavirus.

Ed Cara, a columnist for the Gizmodo portal, understood what is known about the experience of creating vaccines against coronaviruses in the past, what we know about the effectiveness of mRNA vaccines, how optimistic the scientists are about the experimental vaccine. Below we provide excerpts from his material.

Anthony S. Fauci, director of the National Institute of Allergy and Infectious Diseases, said that starting research on a new vaccine in record time is an important first step to success. But not all scientists shared his enthusiasm.

Some scientists have criticized how quickly clinical trials were launched. An experimental vaccine has not been tested in animals, which are usually done before clinical trials (tests on humans). Animal experiments are not required by law, but rather an unspoken rule. Bypassing such rules, even in crisis situations, according to some experts, puts people's lives at risk.

Previously, scientists attempted to create a vaccine against severe acute respiratory syndrome (SARS, SARS), the causative agent of which also belongs to the coronavirus family. The study was stopped due to the fact that the experimental vaccine caused an excessive immune response in laboratory animals. After such vaccination, animals with SARS could become more ill than usual. In theory, a new type of vaccine should not cause such problems, but animal studies could increase the level of human safety.

The production methodology of the mRNA-1273 vaccine may also raise questions. A "regular" vaccine contains any fragments of the virus to "train" the human immune system. There are no such components in vaccines with mRNA.

In theory, mRNA vaccines have advantages over "old-style" vaccines. They are expected to be cheaper, easier and faster to manufacture, and can be developed against a wider range of infections. But in practice, no mRNA vaccine has yet been approved for use, most of them are in early research phases. That is, the technology behind them is poorly studied in practice.

The mRNA-1273 vaccine is not the only candidate. Vaccine options are offered by many scientific groups. One is the group of Peter Hotez, dean of the National School of Tropical Medicine at Baylor College of Medicine.

“I am more optimistic about our vaccine as it uses the studied technologies that licensed vaccines have already given, including the hepatitis B and HPV vaccines,” Hotez told Gizmodo. His group has already successfully tested their vaccine in animals.