The U.S. is getting another COVID-19 vaccine choice as the Food and Drug Administration on Wednesday cleared Novavax shots for adults. Novavax makes a more traditional type of shot than the three other COVID-19 vaccines available for use in the U.S. -- and one that’s already available in Europe and multiple other countries. Nearly a quarter of American adults still haven’t gotten their primary vaccinations even this late in the pandemic, and experts expect at least some of them to roll up their sleeves for a more conventional option — a protein-based vaccine. The Maryland company also hopes its shots can become a top booster choice in the U.S. and beyond. Tens of millions of Americans still need boosters that experts call critical for the best possible protection as the coronavirus continues to mutate. For now, the FDA authorized Novavax’s initial two-dose series for people 18 and older. “I encourage anyone who is eligible for, but has not yet received, a COVID-19 vaccine to consider doing so,” FDA Commissioner Dr. Robert Califf said in a statement. Before shots begin, the Centers for Disease Control and Prevention must recommend how they should be used, a decision expected next week. Novavax CEO Stanley Erck told The Associated Press that he expected the U.S. to expand use of the vaccine beyond unvaccinated adults fairly quickly. Read: Bangladesh gets another 4 mn doses of COVID-19 vaccine from US Already the FDA is evaluating it for those as young as 12, Erck said. Novavax also has submitted data on booster doses, including “mix-and-match” use in people who’d earlier received Pfizer or Moderna vaccinations. The Biden administration has bought 3.2 million Novavax doses so far, and Erck said vaccinations should begin later this month. Sharon Bentley of Argyle, Texas, is one of the holdouts. Bentley was hesitant about the first COVID-19 vaccines but then her husband volunteered for a Novavax trial, getting two doses and later a booster. Her husband’s positive experience with a more tried-and-true technology, “that convinced me,” Bentley said, adding that she planned to tell some unvaccinated friends about the option, too. The Novavax vaccine is made of copies of the spike protein that coats the coronavirus, packaged into nanoparticles that to the immune system resemble a virus. Then an immune-boosting ingredient, or adjuvant, that’s made from the bark of a South American tree is added that acts as a red flag to ensure those particles look suspicious enough to spark a strong immune response. Protein vaccines have been used for years to prevent hepatitis B, shingles and other diseases. It’s a very different technology than the dominant Pfizer and Moderna COVID-19 vaccines that deliver genetic instructions for the body to produce its own copies of the spike protein. The lesser-used Johnson & Johnson option uses a harmless cold virus to deliver spike-making instructions. Like the other vaccines used in the U.S., the Novavax shots have proved highly effective at preventing COVID-19′s most severe outcomes. Typical vaccine reactions were mild, including arm pain and fatigue. But FDA did warn about the possibility of a rare risk, heart inflammation, that also has been seen with the Pfizer and Moderna vaccines. The Novavax vaccine was tested long before the omicron variant struck. But last month, the company released data showing a booster dose promised a strong immune response even against omicron’s newest relatives — preliminary evidence that several of the FDA’s scientific advisers called compelling.

Biotechnology company Novavax said Monday that Indonesia has given the world's first emergency use authorization for its COVID-19 vaccine, which uses a different technology than current shots. The vaccine is easier to store and transport than some other shots, which could allow it to play an important role in boosting supplies in poorer countries around the world. The two-dose Novavax vaccine is made with lab-grown copies of the spike protein that coats the coronavirus. That’s very different from widely used mRNA vaccines such as Pfizer and Moderna that deliver genetic instructions for the body to make its own spike protein. Read: Indonesia prison fire kills 41 drug inmates, 80 hospitalized The emergency authorization of the vaccine is a “very important step” for Indonesia's COVID-19 vaccination program, Indonesian epidemiologist Dicky Budiman said. “This vaccine will be much easier to transport, store and distribute in a place like Indonesia, where we have many islands,” he said. Budiman said if the rollout of the vaccine is successful, it could lead to its approval and use in other developing nations. The need for more vaccines remains critical in many countries, including Indonesia. In June, U.S.-based Novavax announced the vaccine had proven about 90% effective against symptomatic COVID-19 in a study of nearly 30,000 people in the U.S. and Mexico. It also worked against variants circulating in those countries at the time, it said. The company said side effects were mild and included tenderness at the injection site, headache, aches and pains and fatigue. In October, it addressed concerns that production of the vaccine had been slowed due to a lack of raw materials and other issues, saying it planned to “achieve a capacity of 150 million doses per month by the end of the fourth quarter” through partnerships with Serum Institute of India, SK Bioscience in South Korea and Takeda in Japan, among others. Novavax said it has already filed for authorization of the vaccine in the United Kingdom, European Union, Canada, Australia, India and the Philippines. Read: Rapid virus spread through Indonesia taxes health workers Indonesia was battered by a deadly wave of COVID-19 fueled by the delta variant and post-holiday travel from June through August. New cases have now dropped, averaging less than 1,000 a day since mid October. About 36% of people in Indonesian have received two doses of a vaccine, and about 58% have received one dose, according to the Ministry of Health. Over 143,400 people have died from the virus in Indonesia. The number is thought to be an undercount due to low testing and tracing.

Can you mix and match two-dose COVID-19 vaccines? It’s likely safe and effective, but researchers are still gathering data to be sure. The authorized COVID-19 shots around the world are all designed to stimulate your immune system to produce virus-fighting antibodies, though the way they do so varies, noted Dr. Kate O’Brien, director of the World Health Organization’s vaccine unit. “Based on the basic principles of how vaccines work, we do think that the mix-and-match regimens are going to work,” she said. Also read: Why do some people get side effects after COVID-19 vaccines? Scientists at Oxford University in the United Kingdom are testing combinations of the two-dose COVID-19 vaccines made by AstraZeneca, Moderna, Novavax and Pfizer-BioNTech. Smaller trials are also ongoing in Spain and Germany. “We really just need to get the evidence in each of these (vaccine) combinations,” O’Brien said. So far, limited data suggests an AstraZeneca shot followed by the Pfizer shot is safe and effective. The combination also appears to come with a slightly higher likelihood of temporary side effects like aches and chills. That might be because mixing and matching different types of vaccines can often produce a stronger immune response, said Lawrence Young, a virologist at the University of Warwick in the United Kingdom. Also read: How long does protection from COVID-19 vaccines last? In some places, health officials already suggest mixing in select circumstances. After the AstraZeneca vaccine was linked to extremely rare blood clots, many European countries including Germany, France and Spain recommended people who got it as a first dose get a Pfizer or Moderna shot as a second dose instead. In Britain and Canada, officials say people should aim to get the same vaccine for their second dose if possible. If they got AstraZeneca as their first shot, they’re advised to get another vaccine only if they have a history of blood clots or other conditions that might put them at higher risk of clots.

Vaccine maker Novavax said Monday its COVID-19 shot was highly effective against the disease and also protected against variants in a large study in the U.S. and Mexico, potentially offering the world yet another weapon against the virus at a time when developing countries are desperate for doses. The two-shot vaccine was about 90% effective overall, and preliminary data showed it was safe, the American company said. That would put the vaccine about on par with Pfizer’s and Moderna’s. While demand for COVID-19 shots in the U.S. has dropped off dramatically and the country has more than enough doses to go around, the need for more vaccines around the world remains critical. The Novavax vaccine, which is easy to store and transport, is expected to play an important role in boosting supplies in poor parts of the world. Read:As COVID-19 cases wane, vaccine-lagging in USA still see risk That help is still months away, however. The company, which has been plagued by raw-material shortages that have hampered production, said it plans to seek authorization for the shots in the U.S., Europe and elsewhere by the end of September and will be able to produce up to 100 million doses a month by then. “Many of our first doses will go to … low- and middle-income countries, and that was the goal to begin with,” Novavax CEO Stanley Erck said. While more than half of the U.S. population has had at least one vaccine dose, less than 1% of people in the developing world have had one shot, according to a data collection effort run in part by the University of Oxford. The Novavax shot stands to become the fifth Western-developed COVID-19 vaccine to win clearance. The Pfizer, Moderna and Johnson & Johnson vaccines are already authorized for use in the U.S. and Europe. Europe also uses AstraZeneca’s formula. Novavax’s study involved nearly 30,000 people ages 18 and up. Two-thirds received two doses of the vaccine, three weeks apart, and the rest got dummy shots. Nearly half the volunteers were Black, Hispanic, Asian American or Native American, and 6% of participants were in Mexico. Altogether, 37% had health problems that made them high risk, and 13% were 65 or older. There were 77 cases of COVID-19 — 14 in the group that got the vaccine, the rest in volunteers who received the dummy shots. None in the vaccine group had moderate or severe disease, compared with 14 in the placebo group. One person in that group died. Read:G-7 leaders agree on vaccines, China and taxing corporations The vaccine was similarly effective against several variants, including the one first detected in Britain that is now dominant in the U.S., and in high-risk populations, including the elderly, people with other health problems and front-line workers in hospitals and meatpacking plants. “These consistent results provide much confidence in the use of this vaccine for the global population,” said Dr. Paul Heath, director of the Vaccine Institute at the University of London and St. George’s Hospital. Side effects were mostly mild — tenderness and pain at the injection site. There were no reports of unusual blood clots or heart problems, Erck said. A study underway in Britain is testing which of several vaccines, including Novavax’s, works best as a booster shot for people who received the Pfizer or AstraZeneca formula. Industry analyst Kelechi Chikere said the Novavax shot could become a “universal booster” because of its high effectiveness and mild side effects. Novavax reported the results in a news release and plans to publish them in a medical journal, where they will be vetted by independent experts. The Gaithersburg, Maryland-based company previously released findings from smaller studies in Britain and South Africa. COVID-19 vaccines train the body to recognize the coronavirus, especially the spike protein that coats it, and get ready to fight the virus off. The Novavax vaccine is made with lab-grown copies of that protein. That’s different from some of the other vaccines now widely used, which include genetic instructions for the body to make its own spike protein. Read:China’s children may be next in line for COVID-19 vaccines The Novavax vaccine can be stored in standard refrigerators, making it easier to distribute. As for the shortages that delayed manufacturing, Erck said those were due to restrictions on shipments from other countries. “That’s opening up,” he said, adding that Novavax now has weeks’ worth of needed materials in its factories, up from just one week. The company has committed to supplying 110 million doses to the U.S. over the next year and a total of 1.1 billion doses to developing countries. In May, vaccines alliance Gavi, a leader of the U.N.-backed COVAX project to supply shots to poorer countries, announced it signed an agreement to buy 350 million doses of Novavax’s formula. COVAX is facing a critical shortage of vaccines after its biggest supplier in India suspended exports until the end of the year. Novavax has been working on developing vaccines for more than three decades but hasn’t brought one to market. Its coronavirus vaccine work is partly funded by the U.S. government. Read: Biden outlines US vaccine-sharing commitment Dr. Peter English, a vaccine expert previously with the British Medical Association, called the Novavax results “excellent news.” English said that because vaccine production is complicated, it’s crucial to have as many shots as possible. “Any minor imperfection in the production plant can shut down the production for days or weeks,” he said in a statement. “The more different manufacturers we have producing vaccine, the more likely it is we will have availability of vaccines.” He said it was also encouraging news that Novavax would be able to adapt its vaccine to any potentially worrying variants in the future if necessary.