Single-dose shooting offers good protection, new hope against coronavirus



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Johnson & Johnson’s long-awaited vaccine appears to protect against COVID-19 all at once – not as strong as some two-dose rivals, but still potentially useful for a world sorely in need of more doses.

J&J said today that in the United States and seven other countries, the single-injection vaccine was 66% effective overall in preventing moderate to severe disease and much more protective – 85% – against more severe symptoms. .

There was some geographic variation. The vaccine worked better in the United States – 72% effective against moderate to severe COVID-19 – compared to 57% in South Africa, where it faced a mutated virus that was easier to spread.

“Playing with just one dose was definitely worth it,” Dr. Mathai Mammen, head of global research for the J & J’s Janssen pharmaceutical unit, told The Associated Press.

With vaccinations off to a rocky start globally, experts were relying on a single-dose vaccine that would increase scarce stocks and avoid the logistical nightmare of getting people to come back for boosters.

But since some other competing vaccines have been shown to be 95% effective after two doses, the question is whether a little less protection is an acceptable compromise to get more vaccines into the guns quickly.

“Frankly, simple is beautiful,” said Dr. Matt Hepburn of Operation Warp Speed, the US government’s vaccination initiative.

The company said within a week it would file for emergency use in the United States and then overseas. It plans to deliver 100 million doses to the United States by June – and a billion doses worldwide by the end of the year. J&J wouldn’t say exactly how much could be shipped as soon as US officials give the green light.

These are the preliminary results of a study of 44,000 volunteers which has not yet been completed. Researchers tracked diseases from 28 days after vaccination – around the time, if participants were given a two-dose variety instead, they would have needed another vaccine.

After day 28, no one who was vaccinated required hospitalization or died, whether they were exposed to “regular COVID or those particularly nasty variants,” Mammen said. When the vaccinees got infected, they got milder illness.

Beating the scourge that has killed more than 2 million people worldwide will require immunizing billions of people, and the vaccines rolled out so far in different countries both require two doses within weeks of each other for full protection. . Initial data is mixed on how exactly all of the different types work, but the injections given by Pfizer and Moderna appear to be around 95% protective after the second dose.

This poses a dilemma: Wouldn’t people with a choice want a vaccine to offer much more protection?

J & J’s Mammen said direct comparisons are difficult because the Pfizer and Moderna vaccines were not tested when the pandemic was so severe, with record levels of hospitalizations and deaths as well as mutant versions of the virus sweeping through some. country.

Dr Anthony Fauci, America’s top infectious disease official, called it a messaging challenge – because the priority is to protect people from hospitalization and death, which J & J’s vaccine appears to do. Especially in places where it’s difficult to get people to come back for their second dose, the single-dose version could play a key role.

Perhaps more importantly is the study’s “wake-up call” that mutant viruses can challenge vaccines. And the best way to prevent more mutations is “to vaccinate as many people as possible,” Fauci said.

All COVID-19 vaccines train the body to recognize the new coronavirus, usually by spotting the spikey protein that envelops it. But they are made in very different ways.

J & J’s shot uses a cold virus like a Trojan horse to transport the spike gene around the body, where cells make harmless copies of the protein to prime the immune system in case the real virus arises. This is the same technology the company used to make a successful Ebola vaccine.

Rival AstraZeneca makes a similar cold virus vaccine that requires two doses. AstraZeneca and J&J vaccines can be stored in a refrigerator, making them easier to ship and use in developing countries than the frozen vaccines manufactured by Pfizer and Moderna.

It’s unclear how well the AstraZeneca version, which is used in Britain and several other countries, works. Tests in Britain, South Africa and Brazil suggest that two doses are around 70% effective, although there are questions about how well the elderly are protected. An ongoing US study may provide more information.

J&J said his vaccine worked consistently in a wide range of people: One-third of participants were over 60 and more than 40% had other illnesses that put them at risk for severe COVID-19, including obesity, diabetes and HIV.

J&J said the vaccine is safe, with reactions similar to other COVID-19 injections, such as fever, that occur when the immune system is reactivated.

Although it released a few details, the company said there were no serious allergic reactions. But sometimes other COVID-19 vaccines trigger such reactions, which can be reversed if treated quickly – and authorities have warned people to be on the lookout for whatever type of vaccine is used.

J&J had hedged its bets with a study of a two-dose version of its vaccine, which is still ongoing.

Today’s interim results follow another vaccine in final testing. Novavax reported this week that its vaccine appears to be 89% effective in a UK study, and that it also appears to work – but not as well – against new mutated versions of the virus circulating in Britain and South Africa. A larger study in the United States and Mexico is still recruiting volunteers.

Wall Street appeared dissatisfied with J&J’s results, with stocks falling 4.2% early in the session, a rare drop for the world’s largest healthcare maker. Shares were down $ 4.07, or 2.4%, to $ 165.09 by mid-morning.

In contrast, tiny Novavax saw its shares soar, climbing 71% to $ 229.72 by mid-morning.



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