On February 27, the United States Food and Drug Administration (FDA) issued emergency use authorization for the Johnson & Johnson Covid-19 vaccine in adults 18 years of age and older. The vaccine is now the third approved for use in the United States, adding another tool to help stymie the Covid-19 pandemic.
Because Johnson & Johnson's vaccine doesn't use mRNA—as the previously approved vaccines from Moderna and Pfizer-BioNTech do—the vaccine provides several practical benefits. Only one dose is needed instead of two, which means fewer vaccination appointments for patients and reduced production demands. And the new vaccine doesn't require super-cold storage; it remains stable in regular refrigeration for three months.
In clinical trials, Johnson & Johnson’s vaccine was 100 percent effective at preventing hospitalization and death related to Covid-19 and boasts a 72 percent efficacy rate at preventing cases of Covid-19. (For comparison, the FDA looks for at least 50 percent efficacy in new vaccines, and a 60 percent effective seasonal flu vaccine is usually worth celebrating, reports STAT News.)
Each new vaccine that is approved means millions more vaccine doses can become available, and each vaccine’s different strengths make them better for regions facing different circumstances.
“It’s highly desirable” to have many vaccine options, says Vanderbilt University infectious disease specialist William Schaffner to reporters at AARP. Having more options means “there would be more vaccine manufacturers working to actually produce the vaccine, and so we could more expeditiously try to vaccinate the population in the United States and beyond.”
Vaccinating many people as fast as possible not only protects those who get vaccinated, but also reduces the virus’ chances to mutate, Andrew Joseph and Olivia Goldhill report for STAT News.
Anthony Fauci, director of the National Institute of Allergy and Infectious Diseases and chief medical advisor to President Joe Biden, explains that it is difficult to directly compare the three vaccines’ efficacy rates because the clinical trials were run at different times and had different goals, per Andy Sullivan at Reuters.
“Don’t get caught up, necessarily, on the number game, because it’s a really good vaccine, and what we need is as many good vaccines as possible,” says Fauci to the New York Times. “Rather than parsing the difference between 94 and 72, accept the fact that now you have three highly effective vaccines. Period.”
The FDA reviewed data from Johnson & Johnson's clinical trial which involved over 43,000 volunteers in South Africa, Mexico, the United States and several South American countries. The vaccine was less effective in South Africa, where a variant of the coronavirus called B.1.351 is prevalent, than in the United States.
Unlike Moderna and Pfizer-BioNTech's vaccines, which deliver mRNA in an oily bubble, Johnson & Johnson's vaccine uses more stable DNA carried in the shell of a common cold virus. The Johnson & Johnson vaccine has strengths that may make it easier to distribute among some communities, compared to Moderna and Pfizer’s vaccines, which both require super-cold storage and two doses, given a few weeks apart. Johnson & Johnson’s vaccine requires only one shot, so there’s no need for a second appointment, or for healthcare providers to follow up.
Moderna and Pfizer-BioNTech's mRNA vaccines require very specific storage and thawing procedures. The Pfizer vaccine, for instance, must be diluted and inverted exactly ten times to mix it before it can be used, reports Maggie Fox for CNN. But since the Johnson & Johnson vaccine can be stored at standard refrigerator temperatures for three months, it is more accessible for small clinics that might not have the specialty freezers needed to store mRNA vaccines.
“That’s going to be huge for rural populations,” says CEO of the National Rural Health Association Alan Morgan to STAT News.
Some experts recommend that providers survey their local communities and request the vaccines that people are most likely to take. That way, the community won't feel like a vaccine is being pushed on them that they don't want.
“It would be a real mistake to distribute J&J solely based on infrastructure,” says Julie Swann, who is head of the department of industrial and systems engineering at North Carolina State University, to STAT News.
As of Sunday, about 49.8 million people in the U.S. had received at least one dose of a two-dose vaccine, and 24.8 million people are fully vaccinated, per the New York Times vaccine rollout tracker. Johnson & Johnson expects to supply about four million doses this week, 20 million doses by the end of March and 100 million by the end of June, per AARP.
Several more vaccines are currently undergoing clinical trials, and AstraZeneca and Novavax are likely to be the fourth and fifth vaccines to become available. And vaccines that have already been approved in adults need to go through additional trials to become available in adolescents and young children.
"There are seven billion people in the world, so we need multiple vaccines to be successful. This is not a race of one developer against another developer—this is a global collaborative effort," says Daniel Barouch, director of the Center for Virology and Vaccine Research at Beth Israel Daeconess Medical Center in a statement. "I probably speak for all the vaccine developers in saying we want all these programs to succeed."