StemCell Therapy

Imagine generating a vaccine for the novel coronavirus from your immune system.

The virus that causes COVID-19 has swept the globe with about 1.3 million infections and 70,000 deaths through Sunday evening.Development of a widely available vaccine can take a year or more while a virus continues its rampage.

Key to the race to develop a vaccine for the new coronavirus is a technology that uses the virus' genetic code to essentially persuade your body to make its own vaccine.

This techniqueis faster than egg-based manufacturing, which produces the majority of annual flu vaccines and led to delays in distributing a vaccine forH1N1 during the 2009 pandemic.

And it's enablingapossible vaccine for the new coronavirus to be developed in record time.

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Its quicker to get started, said Clem Lewin, who is working onvaccine candidates for the manufacturer Sanofi Pasteur. All you need is the blueprint for the protein."

Testing still will take time. Scientists must determine whether any of several vaccine candidates fight the virus effectively. If so, they need to determine the proper dose. This tinkering is what could take a year or more.

When the first potential vaccine from the manufacturer Moderna was injected into people on March 16, Anthony Fauci, director of the National Institute of Allergy and Infectious Diseases, said he believed the coronavirus vaccine was being developed at a record pace. It took 63 days to go from identifying a viruss genetic sequence to testing a vaccine in people.

Scrambling egg-based production

Several manufacturers pursuing a vaccine for the latest coronavirus have been aided by a technological innovation.

The method that Moderna, Sanofi and others are pursuing is different from traditional vaccinations, in which a weakened or dead version of the virus is introduced into the body, triggering itto createantibodies that would attack the live virus should the person be exposed to it.

In the new approach, pieces of messenger RNA that hold the chemical template of a spike protein from the SARS-CoV-2 virus are injected into a human, said Mark Slifka, a professor of viral immunology at Oregon Health and Science University in Portland, Oregon.

The spikes are what the virus uses to attach to a human cell the first step in sickening someone.

In response to the injection of those molecules, the cells in the body produce the spike protein encoded by that mRNA. That triggers the body tomountan immune response to that viral protein, just as in traditional vaccines.

Essentially, the patient makes their own vaccine, says the narrator of a Moderna video about the vaccine.This cuts out the middleman.

Fauci said volunteers would be given two injections of the potential coronavirus vaccine, the second after 28 days. The doses are 25 milligrams, 100 milligrams and 250 milligrams, he said.

The individuals will be followed for one year both for safety and whether it induces the kind of response that we predict would be protective, Fauci said.

Moderna, the manufacturer conducting the initial tests, projected the first commercially available vaccine in 12 to 18 months. A corporate filing March 23 said CEO Stephane Banceltold Goldman Sachs it is possible that under emergency use, a vaccine could be available to some people, possibly including healthcare professionals, in the fall of 2020.

Why change the menu from reliable eggs?

Most flu vaccines are produced from fertilized chicken eggs, a decades-old process that takes four to five months.The mRNA process ismuch faster.

Delays in producing an H1N1 vaccine spurred health officials to urge development of other technologies, according to a Government Accountability Office report.

Its a state-of-the-art technology for the 1950s, Luciana Borio, then director for medical and biodefense preparedness at the National Security Council, said at a 2018 conference on the 100th anniversary of the Spanish flu pandemic.

A New England Journal of Medicine review of the response to H1N1 found that 78 million doses of the vaccine were eventually produced for 70 countries worldwide, but only after two waves of the illness worldwide.

The most serious operational shortcoming ...was the failure to distribute enough influenza vaccine in a timely way, the report said. The cause: distribution problems, "a shortfall in global vaccine-production capacity and technical delays due to reliance on viral egg cultures for production.

Developing a vaccine is laborious, said Harvey Fineberg, a former president of the U.S. Institute of Medicine and former dean of the public-health faculty at Harvard University.

One step is confirmingthat a possible vaccine doesn't causebad reactions in patients. Then scientists examine how much vaccine is required for an antibody response. And they must verify the vaccine actually protects against infection, which is why it's ideal to test during an outbreak.

All those steps come after scientists identifythe genetic sequence to target for a vaccine.

Its like saying,'Ive got my architectural plans my house must be ready to move into,' Fineberg said. There are a lot of things you need to do between now and being ready to open the door.

Manufacturers work with government

The manufacturers pursuing coronavirus vaccines are working closely withthe Centers for Disease Control and Prevention, the Food and Drug Administration, the National Institute of Allergy and Infectious Diseases and the Biomedical Advanced Research and Development Agency.

Moderna is working on 13 potential vaccines. Sanofi is working on two candidates:an mRNA candidate with the company Translate Bio and another option in collaboration with the Biomedical Advanced Research and Development Agency.

Other companies are pursuing other technologies. GlaxoSmithKline is working with China-based Clover Biopharmaceuticals through a different process to produce a cell-based vaccine.

Johnson & Johnson, which is working on several possible vaccines,announced last week it wouldinvest$1 billion for vaccine research, development and testing. The company said it could produce 1 billion doses of a vaccine when the time comes.

Sen. Chris Coons, D-Del., said $3.5 billion in the coronavirus spending packagewill help develop manufacturing technologies to ensure a robust, agile, U.S.-based supply chain of vaccines, therapeutics, and active pharmaceutical ingredients.

The biggest challenge we face in the United States is not developing a vaccine, tricky as that step is, Coons said in a statement. Its that we lack the domestic manufacturing capacity to quickly produce a vaccine once its proven and deliver it to the American people.

Lewin of Sanofi said the global health emergency spurred manufacturers to try different technologies.

We and all the other manufacturers are working as quickly as possible to accelerate these programs while ensuring the vaccine is safe and effective, Lewin said. It isnt business as usual for anybody.

What about changes to flu vaccines?

The technology used todevelop a coronavirus vaccine wont affect the annual flu vaccine because they are different viruses requiring different approaches. But evenbefore the pandemic,steps were underwayto hasten changes to the flu vaccine.

President Donald Trump signed an executive orderin September calling onmanufacturers to move away from egg-based vaccines because of critical shortcomings, including the months they take to produce. The order anticipated a pandemic more lethalthanthe 1918 Spanish flu, which killed 675,000 Americans.

William Schaffner, professor of infectious diseases at Vanderbilt University, said one reason tochange vaccine productionis that growing the vaccine in eggs allows mutationsthat make it less effective.

People were working on this already, Schaffner said. That sort of commitment, a presidential commitment, plus the moneys that go with it, really put the pedal to the metal for future research.

Egg-based vaccine manufacturing has been reliable. Developing another process would require a multimillion-dollar investment in an industry with small profit margins, Schaffner said.

Moving away from egg-based production is not like flipping a switch, he said. Im sure all the manufacturers are all thinking about this, but how and how quickly they do it is another matter.

Other options include cell-based and recombinant processes. A cell-based vaccine is grown in a mammal's cells, such as kidney cells from monkeys or dogs, rather than in a hen's eggs. A recombinant vaccine is created synthetically from the DNA, or genetic instructions, of a protein from the flu virus. The DNA is then combined with a baculovirus, which infects invertebrates.

Other changes could address vaccine delivery, perhaps moving from injections to pills or skin patches, Schaffner said.

A loftier goal is to develop what is called a universal vaccine, which could last five years at a time. Such a vaccine could be administered any time of year during a doctor's visit, rather than just in the fall.

Doing that would require changing how the vaccine attacks the flu virus, whichis shaped like a sphere with lollipops protruding from it. Vaccines so far have targeted the candy at the end ofthe lollipop, which changes every year.

A vaccine that targetsthe stem of the lollipop could offer protection for years, Shaffner said. If you get vaccinated, youre vaccinated against a whole series of different influenza viruses,Schaffner said.

The coronavirus pandemic has come during a severe flu season. This years vaccine is about as effective as usual, according to a Centers for Disease Control and Prevention study of cases through Feb. 8. The study found the severity for people up to 49 years old including hospitalizations was worse than other recent seasons, including the severe year of 2017-2018.

Current influenza vaccines are providing substantial public health benefits,"said the study in CDCs Morbidity and Mortality Weekly Report."However more effective vaccines are needed."

Contributing:Elizabeth Weise

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A coronavirus vaccine is being developed in record time. But dont expect that technology to speed up flu vaccines yet. - Columbia Daily Herald

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