A COVID-19 single-shot vaccine from Johnson & Johnson was 66 percent effective in preventing moderate or severe disease in a phase 3 clinical trial, a level of protection above the Food and Drug Administration's (FDA) minimum but lower than the authorized Pfizer and Moderna vaccines.
There is also a warning sign from the variant found in South Africa. The efficacy dropped from 72 percent in the United States to 57 percent in South Africa, where a new coronavirus variant is prevalent.
That new variant has been more resistant to vaccines, including now this one, causing concern among experts. Still, a range of vaccines will likely provide protection against the variant.
The company plans to file for authorization from the FDA in "early February," meaning the vaccine could soon add to the U.S. arsenal against the virus.
The company emphasized that its vaccine is 85 percent effective in preventing severe disease and was 100 percent effective in preventing hospitalization or death starting 28 days after vaccination. That is a crucial point, meaning that even if the vaccine is somewhat less effective in preventing people from getting sick at all, it still appears to protect well against people having to go to the hospital or dying.
The overall level of 66 percent is below the roughly 95 percent for Pfizer and Moderna. But it is well above the FDA minimum of 50 percent for authorization.
The Johnson & Johnson vaccine only requires one dose, as opposed to the two-dose vaccines from Pfizer and Moderna, meaning it will be easier to distribute.
The company said it is on track to meet its commitment of 100 million doses for the U.S. by the end of June, though officials declined to provide a timeline for how many doses would be available immediately upon authorization.
“For severe disease, it’s looking really good," National Institutes of Health Director Francis Collins said of the Johnson & Johnson vaccine on a press call. He acknowledged that the South African variant had made it “tougher.
Anthony FauciAnthony FauciIntercept reporters discuss gain-of-function research The Hill's 12:30 Report - Presented by Facebook - DC prepares for Saturday of festivals & Jan. 6 demonstration United Airlines CEO says employees exempt from vaccine 'won't be in front of customers' MORE, the United States' top infectious diseases official, stressed a similar point about the strong efficacy against the worst outcomes.
“If you can prevent severe disease in a high percentage of individuals, that will alleviate so much of the stress and human suffering and death,” he said.
Still, he noted that the drop-off in efficacy against the South African variant is “a wakeup call for us to be nimble and to be able to adjust.”
Vaccines can be updated to specifically address that variant, and mRNA vaccines, which include the Pfizer and Moderna products, are particularly suitable to updating.
Experts say the best way to prevent further mutations and more potentially dangerous variants is for people to get vaccinated as quickly as possible because more people immune means less chance for the virus to spread and evolve.
People should also continue precautions like wearing masks, avoiding indoor gatherings and staying six feet apart.
The safety data from Johnson & Johnson was also strong, the company said, with only a few cases of mild temporary side effects like fatigue or fever, and many people having no side effects at all.
Updated at 9:23 a.m.