Summer can determine the fate of lead shots in the virus vaccine race

Summer can determine the fate of lead shots in the virus vaccine race

People on six continents are already getting injections as the race for a COVID-19 vaccine enters a defining summer, with even bigger studies ready to prove if a shot actually works – and perhaps offer a reality check.

British and Chinese researchers are already chasing the coronavirus across their borders and testing potential vaccines in Brazil and the United Arab Emirates because there are not enough new infections at home to get clear answers.

The US will open the largest trials: 30,000 people test a government-shot from July, followed about a month later by another 30,000 to test a UK.

Those are likely to be distributed to Americans and volunteers in other countries such as Brazil or South Africa, Dr. Anthony Fauci of the National Institutes of Health to The Associated Press.

Although optimistic, “we were burnt before,” Fauci warned.

Multiple successes, in multiple parts of the world, are vital.

“This is not a first-come race. This is, get as many approved, safe and effective vaccines as possible, ‘said Fauci.

Vaccine experts say it’s time to set public expectations. Many scientists don’t expect a coronavirus vaccine to be nearly as protective as the measles shot.

If the best COVID-19 vaccine is only 50% effective, “that’s still a great vaccine to me,” said Dr. Drew Weissman of the University of Pennsylvania.

“We need to start this conversation now,” so people won’t be surprised, he added.

And for all the government’s promises of saving doses hoping to start vaccinations by the end of the year, here’s the catch: even if a shot comes out – and it’s a shot your country has saved – just a few risky people, such as essential workers, go to the front of a really long line.

“Will you and I be vaccinated this year? Absolutely not, ”said David Ridley, health economist at Duke University.

THE HOME RACK

Vaccines train the body to quickly recognize and repel an invading germ. About 15 experimental COVID-19 vaccines are in various stages of human studies worldwide.

And while there’s no guarantee that anything will work, moving three different strains to the latest tests offers better opportunities – especially since scientists don’t yet know how much an immune response the sparks need to spark to protect.

Measuring that with the first proven vaccine “will really help us understand all other vaccines in development, they also have a chance,” said Sarah Gilbert, principal investigator at Oxford University.

Only China is pushing out “inactivated” vaccines created by growing and killing the new coronavirus. Vaccines from Sinovac Biotech and SinoPharm use that old-fashioned technology, which requires highly secured laboratories to produce, but which are reliable, the way polio images and some flu vaccines are made.

Most other vaccines in the pipeline do not target the entire germ, but an important component – the ‘spike’ protein that pollinates the surface of the coronavirus and helps invade human cells. Leading candidates are using new technologies that make shooting faster, but have not yet been proven in humans.

Oxford’s method: Genetically engineer a chimpanzee cold virus so it doesn’t spread, but can transport the gene for that spike protein into just enough cells to mislead the immune system causing an infection.

Another vaccine made by the NIH and Moderna Inc. simply injects a piece of the genetic code of the coronavirus that instructs the body to make harmless spike copies that the immune system learns to recognize.

HUNTING THE VIRUS

Researchers have to test thousands of people, not where COVID-19 is rising – because it’s too late then – but where it is smoldering, Fauci said.

Only if the virus begins to spread through a community a few weeks after volunteers receive a vaccine or dummy injection – time enough for the immune system to develop – will scientists have the best chance of comparing which group had more disease.

In the absence of a crystal ball, the NIH has vaccine testing networks in the US, South America and South Africa that are on standby and finalize decisions on summer testing.

“We’re going to do it across multiple sites with a degree of flexibility,” so researchers can quickly switch as the virus moves, Fauci said. “Nothing is going to be easy.”

The Oxford recording, with a study of 10,000 people underway in England, already ran into that hurdle. Gilbert told a parliamentary committee last week that there is “frankly” little chance of proving the vaccine’s effectiveness in Britain after lockdown infections had fallen.

So her team looked abroad. In addition to the planned study conducted by the U.S., Brazil began a last-stage test of the Oxford shot on 5,000 health workers last week, the first experimental COVID-19 vaccinations in South America. In another scoop, South Africa opened a smaller safety study of the Oxford shot.

With few new infections in China, Sinovac will begin testing on 9,000 Brazilian volunteers next month. And SinoPharm has just signed an agreement with the United Arab Emirates; the scope of that study is not clear.

EXPECT AN INCORRECT PROTECTION

Animal research suggests that COVID-19 vaccines can prevent serious illnesses, but may not completely block the infection. A study dribbling the coronavirus in monkeys found that vaccinated animals avoided pneumonia, but a virus lurked in their nose and throat. Whether it was enough to spread to the non-vaccinated is unknown.

However, that would be a great victory.

“My expectations have always been that we will get rid of symptomatic diseases. From what we’ve seen so far from the vaccines, that’s what they do, ”said Penn’s Weissman.

The first vaccines could be replaced with later, better arrivals, as historically happens in medicine, Duke’s Ridley noted.

And while shots in the arm are the quickest to make, those for respiratory diseases need virus-fighting antibodies to get into the lungs. Gilbert said Oxford will eventually investigate nasal delivery.

WARNING AGAINST DISCOUNTS

Some US lawmakers are concerned about the pressure from the Trump administration to give an unproven shot during the fall election season.

“We want a vaccine, not a head,” Senator Jack Reed, a Rhode Island Democrat, said at a recent Senate committee hearing.

Dr. Stephen Hahn, commissioner of the Food and Drug Administration, promised to a House committee last week that any decision would be science-based.

Different countries have different rules about when to release a vaccine. For the US, Fauci insisted that there should be no safety shortcuts, a major reason why NIH is investing in such massive investigations.

Regardless of how and when a vaccine arrives, each country will also prioritize first in line as doses become available. Presumably they will start with health professionals and those most vulnerable to serious illnesses – as long as every shot has been proven to work in at-risk groups such as older adults.

Because each vaccine works differently, “which population group will protect it, we don’t know yet,” said Dr. Mariangela Simao of the World Health Organization, who advises countries on their choice.

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The Associated Press Health and Science Department is supported by the Department of Science Education of the Howard Hughes Medical Institute. The AP is solely responsible for all content.

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