Johnson & Johnson one-dose vaccine not as efficient as others | Coronavirus pandemic Information
Johnson & Johnson’s long-awaited vaccine appears to protect against COVID-19 with just one shot – not as powerful as some two-shot rivals, but potentially helpful for a world in dire need of more doses.
J&J said Friday that in the United States and seven other countries, the single-shot vaccine was a total of 66 percent effective at preventing moderate to severe illness and, at 85 percent, much more protective against the most serious symptoms.
There were some geographic differences. The vaccine worked better in the US – 72 percent effective against moderate to severe COVID-19 – compared to 57 percent in South Africa, where it competed against an easier-to-spread mutant virus.
“Playing with a dose was definitely worth it,” said Dr. Mathai Mammen, global head of research at J & J’s Janssen Pharmaceutical Unit, told The Associated Press.
With vaccinations getting off to a rocky start around the world, experts had reckoned on a vaccine at a dose that would stretch the scarce supplies and avoid the logistical nightmare of getting people to return for boosters.
However, with some other competing vaccines that have been shown to be 95 percent effective after two doses, the question is whether a little less protection is an acceptable compromise for getting more shots in the arms quickly.
The company said within a week it would file an emergency claim in the US and then overseas. The US is expected to receive 100 million cans by June, and some are expected to be ready for shipping once the authorities give the green light.
These are preliminary results from a study of 44,000 volunteers that is ongoing. Researchers tracked diseases that began 28 days after vaccination – around the time when participants, if given a two-dose variety instead, would have needed another shot.
After day 28, no one who was vaccinated needed hospitalization or died, regardless of whether they were exposed to “normal COVID or those particularly nasty variants,” Mammen said. When the vaccinated became infected, they had a milder disease.
Many Americans have made efforts to gain access to the vaccine in the state through government introductions [Lauren Justice/Reuters]To defeat the Scourge, which has killed more than two million people worldwide, billions will need to be vaccinated, and the shots that have so far been carried out in different countries require every two doses a few weeks apart for complete protection. Early data is mixed up exactly on how well the different types work, but shots from Pfizer and Moderna appear to be about 95 percent protective after the second dose.
However, due to shortages, some countries have recommended delaying the second dose of certain vaccines, with little data on how this would affect protection.
All COVID-19 vaccines train the body to recognize the new coronavirus, usually by recognizing the spikey protein that covers 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 into the body, where cells make harmless copies of the protein to activate the immune system in the event the real virus occurs.
Rival AstraZeneca makes a similar cold virus vaccine that requires two doses. Both the AstraZeneca and J&J vaccines can be refrigerated, making them easier to ship and use in developing countries than Pfizer and Moderna’s frozen vaccines.
It’s not exactly clear how well the AstraZeneca version used in the UK and several other countries works. Tests in the UK, South Africa and Brazil have found two doses to be around 70 percent effective, although questions exist about how much protection older adults get. An ongoing US study could provide more information.
J&J said its vaccine worked consistently across a wide range of people: a third of participants were over 60 years old, and more than 40 percent had other diseases that put them at risk for severe COVID-19, including obesity, Diabetes and HIV.
J&J said the vaccine was safe, with reactions similar to other COVID-19 shots, such as: B. Fever, which occurs when the immune system is restored.
Although few details were released, the company said it did not experience any serious allergic reactions. Occasionally, however, other COVID-19 vaccines trigger such reactions that can be reversed with immediate treatment. Authorities have warned people to keep an eye out regardless of the type of vaccine used.
J&J had hedged its bets with a study of a two-dose version of its vaccine that is still ongoing.
The interim results from Friday follow another vaccine in the final test. Novavax reported this week that its vaccine appears 89 percent effective in a UK study and that it also appears to work, albeit not as well, against new mutated versions of the virus circulating in the UK and South Africa. Volunteers are still being enrolled in a larger study in the US and Mexico.