Novavax’s Vaccine Works Well — Except on Variant First Found in South Africa
An early analysis in Britain found that the vaccine had an efficacy rate of nearly 90 percent. But in a small South Africa trial, the efficacy rate dropped to just under 50 percent.
By Katie Thomas, Carl Zimmer and Sharon LaFraniere
Novavax, a little-known company supported by the U.S. federal government’s Operation Warp Speed, said for the first time on Thursday that its Covid-19 vaccine offered robust protection against the virus. But it also found that the vaccine is not as effective against the fast-spreading variant first discovered in South Africa, another setback in the global race to end a pandemic that has already killed more than 2.1 million people.
The news was problematic for the United States, which hours earlier reported its first known cases of the contagious variant in two unrelated people in South Carolina. And it came just days after Moderna and Pfizer said that their vaccines were also less effective against the same variant.
Novavax, which makes one of six vaccine candidates supported by Operation Warp Speed last summer, has been running trials in Britain, South Africa, the United States and Mexico. It said Thursday that an early analysis of its 15,000-person trial in Britain revealed that the two-dose vaccine had an efficacy rate of nearly 90 percent there. But in a small trial in South Africa, the efficacy rate dropped to just under 50 percent. Almost all the cases that scientists have analyzed there so far were caused by the variant, known as B.1.351. The data also showed that many trial participants were infected with the variant even after they had already had Covid.
“We have the first trial — we are the first to conduct an efficacy trial — in the face of a changing virus,” said Stanley Erck, the president and chief executive of Novavax. He said that researchers expected the variants could change the trial results, but “the amount of change has been a bit of a surprise to everyone.”
The South Africa trial was relatively small — with just 4,400 volunteers — and was not designed to come up with a precise estimate of how much protection the vaccine provides. Still, the results were striking enough that the company said it would soon begin testing a new vaccine tailored to protect against the variant from South Africa. “You’re going to have to make new vaccines,” Mr. Erck said.
While the Pfizer and Moderna vaccines rely on a newer mRNA technology that has not been used in previous vaccines, Novavax’s candidate employs an older, more established method that relies on injecting coronavirus proteins to provoke an immune response.
How the Novavax Vaccine Works
Using a coronavirus protein to train the immune system.
The fact that three vaccines all appeared to show lowered effectiveness against the variant from South Africa is not encouraging, and the results Novavax announced Thursday were the first to occur outside of a laboratory, testing how well a vaccine worked in people infected with a new variant. Johnson & Johnson is also on the cusp of announcing results of its Covid-19 vaccine trials, and has also tested its candidate in South Africa.
The announcement from Novavax raises the stakes for Johnson & Johnson. The company was expected to announce its results as early as last weekend, and the delay has triggered speculation among scientists that the firm has also discovered that its vaccine worked less well in South African trial volunteers who were infected with the variant. In an earnings call on Tuesday, Alex Gorsky, the chief executive officer of the company, said they were looking forward to sharing results from their late-stage trial by early next week.
The emergence of several highly contagious variants has complicated efforts to bring the pandemic under control, leading world leaders to shut down travel to places like Britain and South Africa even as the variants already appear to have circled the globe. In the United States, researchers have warned that the variant first identified in Britain, which is believed to be more infectious, could become the dominant form of the virus in this country by March.
The United States is well behind other countries in testing for such variants, and the one from South Africa has been found in about 30 countries.
But experts have also said there are reasons for optimism, noting that the vaccines remain effective. The best way to combat contagious new variants is to continue vaccination and other public health measures, which will slow the virus’s ability to infect new people and mutate further. Drug makers could update their vaccines and offer new shots at regular intervals, similar to the flu vaccine.
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Answers to Your Vaccine Questions
Currently more than 150 million people — almost half the population — are eligible to be vaccinated. But each state makes the final decision about who goes first. The nation’s 21 million health care workers and three million residents of long-term care facilities were the first to qualify. In mid-January, federal officials urged all states to open up eligibility to everyone 65 and older and to adults of any age with medical conditions that put them at high risk of becoming seriously ill or dying from Covid-19. Adults in the general population are at the back of the line. If federal and state health officials can clear up bottlenecks in vaccine distribution, everyone 16 and older will become eligible as early as this spring or early summer. The vaccine hasn’t been approved in children, although studies are underway. It may be months before a vaccine is available for anyone under the age of 16. Go to your state health website for up-to-date information on vaccination policies in your area
You should not have to pay anything out of pocket to get the vaccine, although you will be asked for insurance information. If you don’t have insurance, you should still be given the vaccine at no charge. Congress passed legislation this spring that bars insurers from applying any cost sharing, such as a co-payment or deductible. It layered on additional protections barring pharmacies, doctors and hospitals from billing patients, including those who are uninsured. Even so, health experts do worry that patients might stumble into loopholes that leave them vulnerable to surprise bills. This could happen to those who are charged a doctor visit fee along with their vaccine, or Americans who have certain types of health coverage that do not fall under the new rules. If you get your vaccine from a doctor’s office or urgent care clinic, talk to them about potential hidden charges. To be sure you won’t get a surprise bill, the best bet is to get your vaccine at a health department vaccination site or a local pharmacy once the shots become more widely available.
Probably not. The answer depends on a number of factors, including the supply in your area at the time you’re vaccinated. Check your state health department website for more information about the vaccines available in your state. The Pfizer and Moderna vaccines are the only two vaccines currently approved, although a third vaccine from Johnson & Johnson is on the way.
That is to be determined. It’s possible that Covid-19 vaccinations will become an annual event, just like the flu shot. Or it may be that the benefits of the vaccine last longer than a year. We have to wait to see how durable the protection from the vaccines is. To determine this, researchers are going to be tracking vaccinated people to look for “breakthrough cases” — those people who get sick with Covid-19 despite vaccination. That is a sign of weakening protection and will give researchers clues about how long the vaccine lasts. They will also be monitoring levels of antibodies and T cells in the blood of vaccinated people to determine whether and when a booster shot might be needed. It’s conceivable that people may need boosters every few months, once a year or only every few years. It’s just a matter of waiting for the data.
Employers do have the right to compel their workers to be vaccinated once a vaccine is formally approved. Many hospital systems, for example, require annual flu shots. But employees can seek exemptions based on medical reasons or religious beliefs. In such cases, employers are supposed to provide a “reasonable accommodation” — with a coronavirus vaccine, for example, a worker might be allowed to work if they wear a mask, or to work from home.
If you have other questions about the coronavirus vaccine, please read our full F.A.Q.
Novavax’s trial in Britain tested how many volunteers developed symptoms of Covid-19 one week after receiving a second dose. The company said Thursday that its initial analysis showed that out of 62 participants who developed the illness, 56 had received a placebo and 6 had gotten the vaccine. The newer, more contagious variant first identified in Britain was found to have caused about 50 percent of the cases in the trial, Novavax said.
If those results were to bear out in the larger clinical trial in the United States and Mexico, which has enrolled about 16,000 out of a goal of 30,000 people, then it would put the vaccine on par with the Moderna and Pfizer-BioNTech vaccines, which were shown to be about 95 percent effective.
But the news in South Africa was not as encouraging. Novavax’s smaller trial found the vaccine to have a 49.4 percent efficacy overall. (The company reported that about 6 percent of the trial’s participants were positive for H.I.V., and for those who were not H.I.V. positive, the vaccine had a 60 percent efficacy.) The company said the trial began recording cases of Covid-19 from September through the middle of this month, when the more contagious variant was widely circulating. Novavax said 44 trial participants developed Covid-19, and it sequenced the genetic lineage of 27 cases. Of those, 25 cases were caused by the more contagious version of the virus.
The company also said that about one-third of the trial participants in South Africa had previously developed Covid-19 after being infected by the original form of the virus, and that their results showed those previous infections did not protect them against the new variant. The company said its vaccine did provide some protection for those who had previously contracted the disease, but did not include this group in its analysis.
Novavax began working on a new version of the vaccine this month to address more contagious variants, which could serve either as a booster shot or which could be given at the same time as their original vaccine.
The B.1.351 variant first came to the attention of scientists in December. It contains a number of mutations, including some that change the shape of the surface of the virus and weaken the effectiveness of vaccines.
Looking back at older samples, South African scientists found the first evidence of B.1.351 dating back to October. But by December, it had swept across the country, becoming the dominant lineage of the coronavirus in many regions.
That alone would make B.1.351 a worrying development. In Britain, researchers found another fast-spreading variant known as B.1.1.7. In Brazil and California, other scientists have found variants that may be more contagious than previous forms of the coronavirus.
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