The demand for COVID-19 vaccines exceeds the global supply, and frustrated populations and governments want to know how to get more. A lot more. Right now.
The problem, said Maria Elena Bottazzi, a vaccine specialist at Baylor School of Medicine, is that “it’s not like adding more water to soup.”
Manufacturers of COVID-19 vaccines need to straighten things out by correcting production at hundreds of millions of doses, and every small failure can lead to a delay. Some of its ingredients have never been produced in the enormous volume needed now.
And the seemingly direct proposals that other factories change their production to make new vaccines cannot be implemented overnight. In the same week, French pharmaceutical company Sanofi announced its unusual decision to help package and package vaccines produced by its competitor Pfizer and its German partner BioNTech. But these doses will not start running until the summer, and Sanofi has the space available at the German factory only because its own vaccine has been delayed, which is bad news for total global supplies.
“We thought, well, well, they’re like men’s shirts, right?” I’ll just have another place to do it, “said Dr. Paul Offit of Philadelphia Children’s Hospital, a U.S. government adviser on vaccines. “It’s just not that easy.”
DIFFERENT VACCINES, DIFFERENT RECIPES
The different classes of vaccines used in different countries train the body to recognize the new coronavirus, mainly the glycoprotein that covers it. But it requires different technologies, raw materials, equipment and knowledge.
The two vaccines licensed in the United States so far, from Pfizer and Moderna, are made by placing a piece of genetic code called mRNA – the instructions for that glycoprotein – in a small ball of fat.
Making small amounts of mRNA in a research lab is easy, but “before that, no one had done a billion doses, not 100 million, not even a million doses of mRNA,” said Dr. Drew Weissman. from the University of Pennsylvania and who contributed to the development of mRNA technology.
Scaling it doesn’t just mean multiplying the ingredients to get more. The creation of mRNA involves a chemical reaction between enzymes and genetic elements, and Weissman noted that enzymes do not work as efficiently in large quantities.
The AstraZeneca vaccine, already used in the UK and other countries, and the one expected to be released by Johnson & Johnson soon, are made from a cold virus that carries the glycoprotein gene in the body. Its manufacture is very different: the living cells of this virus are cultured in huge bioreactors, before being extracted and purified.
“If cells age or get tired or start to change, you can get less,” Weissman said. “There are many more variables and many other things you need to check.”
A more classic variety, “inactivated” antivirus vaccines such as the one made by Sinovac in China, require even more steps and increased biosecurity, because they are made from killed coronaviruses.
There is something in common with all vaccines: they must be manufactured in accordance with strict regulations that require facilities that pass specific inspections and with checks at each stage, which are time consuming but necessary to have confidence in the quality of all shipments.
WHAT ABOUT THE SUPPLY CHAIN?
Production depends on obtaining sufficient raw material. Pfizer and Moderna insist they have reliable suppliers.
However, a US government spokesman said logistics experts are working directly with vaccine manufacturers to anticipate and resolve any supply problems.
Moderna CEO Stephane Bancel acknowledges that challenges remain.
The company maintains production 24 hours a day, so that if one day “a material is missing, we can’t start producing products, and that capacity will be lost forever because we can’t compensate for it,” he explained recently. investors.
Pfizer has temporarily reduced deliveries to Europe for several weeks to improve its Belgian plant and increase production.
And sometimes remittances are short. AstraZeneca told the outraged European Union that his company would initially deliver fewer doses than promised. Reason quoted: lower-than-expected production in some production centers in Europe.
More than in other industries, when you work with organic ingredients, “there are things that can go wrong and will go wrong,” said Norman Baylor, former director of vaccines at the U.S. Food and Drug Administration (FDA). its in English) and that it described production variations as common.
HOW MUCH IS IT DONE?
That varies by country. Moderna and Pfizer expect to deliver 100 million doses in the United States by the end of March and another 100 million in the second quarter of the year. As president, Joe Biden announced plans to buy even more in the summer to vaccinate 300 million Americans in total.
Pfizer CEO Albert Bourla told a Bloomberg conference this week that his company will deliver 120 million doses by the end of March, not because production is accelerating, but because medical staff are now allow an additional dose to be removed from each vial.
But getting six doses instead of five requires the use of specialized syringes and there are questions about the overall supply. The United States delivers batches of special syringes at each shipment from Pfizer, a spokesman for the Department of Health and Human Services said.
Pfizer also said upgrades to its plant in Belgium are causing problems for long-term benefits, as the changes will help increase global production to 2 billion doses this year instead of the 1.3 billion originally planned.
Moderna also recently announced that it will be able to deliver 600 million doses of vaccine in 2021, compared to the 500 million originally planned and that it is expanding its capacity to reach 1 billion.
But probably the easiest way to get more doses is to see that other developing vaccines have been shown to work. US data on the effectiveness of the single-dose drug Johnson & Johnson are expected soon, and another company, Novavax, is in the final stages of its studies.
OTHER OPTIONS
For months, major vaccination companies have signed “manufacturer contracts” in the United States and Europe to help them produce the doses and complete their packaging. Moderna, for example, works with the Swiss Lonza.
Outside the rich countries, the Serum Institute of India has a contract to manufacture 1 billion doses of AstraZeneca vaccine. It is the largest producer of vaccines in the world and is expected to be a key supplier to developing countries.
But some local supply-side efforts seem to be in trouble. Two Brazilian research institutes expect to produce millions of doses of AstraZeneca and Sinovac vaccines, but have suffered inexplicable delays in supplying ingredients from China.
In addition, Bottazzi said, the world must continue to produce vaccines against polio, measles, meningitis and other diseases that continue to hide during the pandemic.
Weissman, an expert at the University of Pennsylvania, called for patience.
“I think we will get more vaccines every month than the previous month,” he said.