Johnson and Johnson 1-dose shot forestalls COVID-19, however not exactly some others

Overview

• Post By : Kumar Jeetendra


• Source: Agencies


• Date: 29 Jan,2021

Johnson & Johnson’s long-awaited vaccine seems to protect against COVID-19 with just 1 shot — not as strong as some two-shot rivals but still potentially helpful for a world in dire need of more doses.

J&J said Friday that in the U.S. and seven other nations, the single-shot vaccine was 66% effective overall at preventing mild to severe disease, and a great deal more protective — 85% — against the most serious symptoms.

There was some geographic variation. The vaccine worked better at the U.S. — 72% effective against moderate to severe COVID-19 — compared to 57 percent in South Africa, where it was up against an easier-to-spread mutated virus.

“Gambling on a single dose was certainly worthwhile,” Dr. Mathai Mammen, global research chief for J&J’s Janssen Pharmaceutical unit, told The Associated Press.

With vaccinations off to a rocky beginning worldwide, experts were counting on a one-dose vaccine that would stretch scarce supplies and prevent the logistics nightmare of getting people to return for boosters.

However, with a few other competing vaccines shown to be 95% effective after two doses, at question is if marginally less protection is an acceptable tradeoff to get more shots in arms fast.

The company said within a week, it will file an application for emergency use in the U.S., and then overseas. It expects to supply 100 million doses to the U.S. by June, and hopes to have some ready to ship as soon as authorities give the green light.

These are preliminary findings from a study of 44,000 volunteers who isn’t completed yet. Researchers tracked disorders starting 28 days after vaccination — about the time when, if participants were getting a two-dose variety instead, they would have needed another shot.

After day 28, no one who got vaccinated needed hospitalization or expired no matter whether they were subjected to”regular COVID or those particularly nasty variants,” Mammen said. When the vaccinated failed to become infected, they had a milder illness.

Defeating the scourge that has killed over 2 million individuals worldwide will require vaccinating billions, and the shots being rolled out in different countries so far all require two doses a few weeks apart for full protection. Early data is blended on exactly how well all the different types work, but shots made by Pfizer and Moderna appear to be about 95% protective after the second dose.

But amid shortages, some countries have advised delaying the second dose of certain vaccines with little data on how that could affect protection.

All COVID-19 vaccines train the body to recognize the new coronavirus, usually by spotting the spikey protein that coats it. But they’re made in very different manners.

J&J’s shot uses a cold virus like a Trojan horse to carry the spike gene into the body, where cells create benign copies of the protein to prime the immune system in the event the real virus comes along.

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

It’s not clear how well the AstraZeneca version, being used in Britain and many other countries, functions. Tests in Britain, South Africa and Brazil suggested two doses are approximately 70% effective although there are questions about just how much protection older adults get. A continuing U.S. study may provide more information.

J&J said its vaccine works consistently in a wide range of individuals: A third of participants were over age 60, and over 40% had other ailments placing them at risk of severe COVID-19, such as obesity, diabetes and HIV.

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

While it released few details, the company said there were no significant allergic reactions. But sometimes other COVID-19 vaccines trigger such responses, which may be reversed if promptly treated — and authorities have warned people to be on the lookout irrespective of which kind of vaccine is used.

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

Novavax reported that its vaccine seems 89% effective in a U.K. research and that it also seems to work — though not too — against new mutated versions of the virus circulating in Britain and South Africa. A larger study in the U.S. and Mexico is still enrolling volunteers.