The one-shot vaccine from Johnson & Johnson now has FDA support in the US

An advisory board to the US Food and Drug Administration voted unanimously in favor of the first single-shot covid-19 vaccine, clearing the path for the health agency to authorize its immediate use as soon as tomorrow.

The one-shot vaccine, developed by Johnson & Johnson, has the additional advantage of being easy to store, because it requires nothing colder than ordinary refrigerator temperatures. It stopped 66% of mild and serious covid-19 cases in a trial carried out on three continents.

It will join a US covid arsenal that already includes authorized vaccines from Moderna and Pfizer. Those vaccines, which use messenger RNA, were significantly more effective (they stopped about 95% of cases), but they require two shots, and the doses need to be stored at ultra-cold temperatures.

Globally, a growing list of injections developed in Russia, China, India, and the United Kingdom all are starting to see wide use.

While the new J&J vaccine isn't as effective as those made using messenger RNA technology, health officials said that shouldn't dissuade people from getting it, since it still sharply reduces the chance of illness and death.

To have two is fine, and having three is absolutely better," Anthony Fauci, the country's chief virologist, said during an interview on NBC. It's more choices and increases the supply. It will certainly contribute to getting control."

In the US, there have been approximately 28 million confirmed cases of covid-19 and 500,000 deaths.

The limited supplies of the Moderna and Pfizer shots mean most Americans are still waiting to be vaccinated. About 1.4 million doses of those two vaccines were given each day last week in the US. At that pace it would take about a year to vaccinate the whole nation.

In theory, an easily stored single-shot vaccine could kick up the pace. In practice, though, supply shortages of the J&J vaccine could limit the role it plays in the US vaccination campaign. In testimony before Congress this week, Johnson & Johnson said it had only 4 million shots ready to go, a third of the initial supply promised, and would deliver only 20 million doses by the end of March.

I wonder if the J&J vaccine is going to be a significant part of the US landscape," says Eric Topol, a doctor at the Scripps Research Institute, who called initial supplies paltry" given that the company received extensive government support.

The vaccine also has what Topol called a notable dropdown in efficacy overall" compared with messenger RNA shots, although many health experts this week rushed to defend the vaccine against any suggestion it was inferior.

Everything we've seen so far says these are excellent vaccines," Ashish Jha, a health policy researcher and doctor at Brown University, wrote on Twitter, where he argued that comparing headline efficacy" among vaccines can be misleading since they all are essentially 100% at preventing hospitalizations [and] deaths once they've kicked in."

New shot

The new one-shot vaccine, called Ad26.COV2.S, was developed by Johnson & Johnson using work from Beth Israel Deaconess Medical Center in Boston. It employs a harmless viral carrier, adenovirus 26, which can enter cells but doesn't multiply or grow. Instead, the carrier is used to drop off gene instructions that tell a person's cells to make the distinctive coronavirus spike protein, which in turn trains the immune system to combat the pathogen.

The New York Times published a detailed graphical explanation of how the vaccine works.

Richard Nettles, vice president of US medical affairs at Janssen, a J&J subsidiary, told Congress during testimony on February 23 that production of the vaccine is highly complex" and said the company was working to manufacture the shots at eight locations, including a US site in Maryland.

The manufacturing is complicated because the vaccine virus is grown in living cells before it is purified and bottled. Making a batch of virus takes two months, which is why there is no way to immediately increase supplies if timelines are missed.

Indeed, the biggest disappointment around the new vaccine is a supply shortfall caused by manufacturing problems. Jeffrey Zients, coordinator of President Biden's covid-19 task force, said during a White House press conference on Wednesday, February 24, that the new administration had only learned that J&J was behind on manufacturing" when it took office five weeks ago.

It was disappointing when we arrived," he said. The initial production ramp ... was slower than we'd like."

Pretty effective

In late January, the company announced results from a 45,000-person study it carried out in the US, South Africa, and South America, in which people got either the vaccine or a placebo.

Overall, the vaccine was 66% effective in stopping covid-19, and somewhat better at stopping severe disease. In the trial, for instance, seven people died of covid-19, but all of these were in the placebo arm. Also, its effects increased with time-after a month, no one in the vaccine arm had to go to the hospital for covid-19.

Johnson & Johnson claims it will not be making a profit from the vaccine, which will also be sold outside the US. Instead, Nettles said, the vaccine will be sold at a single not-for-profit" price to all countries for emergency pandemic use."

Nettles didn't say what that price would be, but the US agreed last year to pay the company about $1 billion for a guarantee of 100 million doses and has given the company a similar amount of development funding, making it one of the major investments of Operation Warp Speed, as the vaccine effort was known during the Trump administration.

Shortage to surplus

At least for the moment, vaccine supply remains a limiting factor in the US inoculation campaign, which has seen 70 million doses administered since it began in December, according to Bloomberg. I don't see an excess of vaccine for a while," says Peter Hotez, a virologist and vaccine developer at the Baylor College of Medicine.

All told, the US will have received enough shots to fully vaccinate 130 million Americans by the end of March, when projected supplies from Pfizer, Moderna, and J&J are tallied together.

Still, vaccine shortages could turn to excess before summer, creating a situation in which it's no longer vaccines that are in short supply, but people willing or eligible to receive them.

That is because in the US, children under 18 make up about a quarter of the population but aren't yet allowed to receive the shots. As well, about 30% of American adults claim they won't get a covid-19 vaccine at all. Children and vaccine doubters together make up half the population.

By August, the three companies say, they will deliver the US enough vaccines for 400 million people, or more than the country's population. That does not account for a fourth vaccine, manufactured by Novavax, that may also win US authorization.

By the summer we will be in good shape. The question is how we navigate this space between now and June," says Hotez.

Growing arsenal

The Johnson & Johnson shot joins a growing worldwide list of approved vaccines that includes the two messenger RNA vaccines, injections from AstraZeneca and Chinese manufacturers, and Russia's Sputnik" vaccine, all of which are in use outside the US.

People who get any of the vaccines will, on average, see their chance of dying from covid-19 plummet to near zero. That is down from an overall death rate of around 1.7% of diagnosed cases in the US-and a risk several times higher in elderly people.

The J&J shot has fewer side effects than the mRNA vaccines and has also proved effective against a highly transmissible South African variant of the virus that has accumulated numerous mutations.

The South Africa variant has alarmed researchers because it clearly decreases the effectiveness of some vaccines. A study in South Africa by AstraZeneca found its vaccine didn't offer protection against the variant at all, causing officials to scrap a plan to distribute the shot there.

According to health minister Zweli Mkhize, South Africa is instead pivoting to the J&J vaccine, with a plan to vaccinate 80,000 health-care workers in the next two weeks.

This week, Moderna also said it would develop a shot tailored against the South African variant, and Pfizer indicated it was also preparing to counter new strains as they arise. Another strategy being contemplated to fend off variants is to give people extra booster doses of the current vaccines.

Some experts in the US continue to urge the government to adopt faster-paced vaccine schemes, like delaying second doses of the messenger RNA shots or using half doses, arguing that the more people who have good enough" protection, the sooner the pandemic will end.

So far, though, it's not clear what agency or official would be ready, or even legally authorized, to make that call.

We are all scratching our heads about who could make that decision," says Hotez. And it all depends on how much urgency you feel. The big picture is if you know the numbers are going down, and feel they are going to stay down due to seasonality, then you have some breathing space. But if you are worried about variants, then you have a problem, and you want to vaccinate ahead of schedule."

On NBC, Fauci said people shouldn't wait for the best vaccine but take what's offered. Even one that may be somewhat less effective is still effective against severe disease, as we have seen with the J&J vaccine," he said. Get vaccinated when the vaccine is available to you."