Two vaccine candidates that claim to be about 95% effective against coronavirus will likely receive FDA authorization in the US this month, with several others not far behind. Here's what that really means.
With less than a month to spare before the calendar flips to 2021, it appears at least two coronavirus vaccines are poised to be dispensed in the US this year. The first comes from US pharmaceutical giant Pfizer, which reported that its vaccine demonstrated 95% effectiveness in clinical trials, applied to the US Food and Drug Administration last week for authorization to begin distribution. Moderna, another US drug developer, said its vaccine is 94% effective before applying for FDA authorization this week as well. Both companies tested an initial dose plus a subsequent "booster" dose several weeks later, with few if any serious side effects reported.
The drugs from Pfizer and Moderna are both experimental RNA vaccines and will most likely be arriving for a limited group of people later this month. Another vaccine developed by Oxford University and biotech firm AstraZeneca has not yet proven as effective as the other two, researchers announced last week. It's likely that Oxford's vaccine -- as well as a handful of others not far behind it -- will also seek FDA authorization in the coming weeks and months. Novavax's vaccine, which some are calling the most promising of the bunch, is currently on hold, but the company says it's still moving ahead with planned phase 3 clinical trials.
Pfizer, if authorized, expects to produce up to 50 million vaccine doses in 2020 and 1.3 billion in 2021. Moderna plans to ship 20 million doses in 2020 and another 500 million to 1 billion in 2021, if authorized. With over 330 million people in the US alone, not everyone will be able to get a vaccine at once -- the first doses to reach the market will likely go to employees and residents of nursing homes as well as front-line health care personnel, followed by essential workers, people with underlying medical conditions and older adults.
Currently, there are several dozen coronavirus vaccines in various stages of clinical trials, with a handful almost ready to apply for authorization. Most experts believe we'll have several more ready to distribute by early 2021, but it may not be until 2022 that life starts to get back to normal.
Here, we walk you through the leading coronavirus vaccine news and explain where the most promising candidates stand. This article is updated frequently and is intended to be a general overview, not a source of medical advice. If you're seeking more information about coronavirus testing, here's how to find a testing site near you.
We probably won't know until next year, but Fauci has suggested we might require several different vaccines made and distributed by different labs to bring an end to the pandemic, in a paper published May 11 in the journal Science. He also has said he foresees different vaccines being given to different patient populations. For example, one vaccine for elderly or other high-risk patients, another for healthy adults and another for children.
Getting one or more vaccines through clinical trials to FDA approval is just the first leg of the journey. The next is convincing people to take it. Sixty-three percent of US adults expressed safety concerns over a coronavirus vaccine, according to a Harris Poll from Oct. 19, with 40% of respondents specifically worrying that development has been too fast. Some people are reportedly concerned about possible side effects.
Life in the US will begin to return to normal once we reach what scientists call "herd immunity," which, with regard to the coronavirus, means at least 60% to 70% of the population is immune. So long as enough people take the vaccine to reach that level, it won't matter if a few people object or decline to take the vaccine for other reasons, for example, if they aren't healthy enough to be vaccinated.
Coronaviruses are a large class of viruses and so far there are no vaccines for any of them. While there are promising early results, there's no guarantee a vaccine will be ready by 2021. Statistically, only about 6% of vaccine candidates ever make it through to market, according to a Reuters report from April. However, health officials are very optimistic that the Pfizer vaccine and others like it could end the coronavirus pandemic.
Whether or not COVID-19 vaccines are effective at stopping the spread of coronavirus will depend a lot on how our bodies build immunity to the disease. Here's what we know so far about whether or not you can get COVID-19 more than once. Testing is also key to slowing coronavirus' spread -- learn about a device that can produce results in under 90 minutes here. Finally, read about how all of these issues and more weigh in on US President-elect Joseph Biden's plan to fight COVID-19.
Here's a quick look at some of the frontrunners besides Pfizer and Moderna in the race to find a vaccine for COVID-19, including where the vaccines are being developed, where they are on testing them and when scientists think they might be ready for widespread distribution, if known.
Oxford University/AstraZeneca (UK): AstraZeneca began testing on 100,000 human volunteers in at least three countries. Lead researcher Dr. Sarah Gilbert had initially said AstraZeneca is aiming for a fall 2020 release and, while that may be optimistic at this point after the trial was briefly paused to investigate a participant's illness, it doesn't appear to be significantly delayed.
Sinovac (China): Currently testing its vaccine on about 10,000 human volunteers in China and about 9,000 in Brazil and is set to begin testing on about 1,900 test subjects in Indonesia soon. Honesti Basyir, the president of Bio Farma, Sinovac's Indonesian partner, has said he expects the vaccine to be ready by early 2021.
Sinopharm (China): Currently testing about 15,000 volunteers in the Middle East in a trial the state-owned company expects to last three to six months. Early results suggest the drug is safe and at least somewhat effective. Sinopharm recently built a second facility to manufacture the vaccine, doubling its capacity to about 200 million doses per year.
CanSino Biologics (China): Set to begin large-scale human trials this summer, CanSino's vaccine has already been approved for the Chinese military. The vaccine is based on a modified common cold virus, which some experts warn could make it less effective than other vaccine efforts.
Several acceleration efforts are currently underway, like the White House's Operation Warp Speed, which is meant to cut through regulatory red tape to speed up vaccine development and be ready to distribute vaccines as soon as they receive FDA authorization. So far, the US government has pledged over $10 billion to several vaccine manufacturers to secure a total of 800 million vaccine doses.
Vaccines typically take about 10 to 15 years to develop and approve, through four phases that include human trials. But with Operation Warp Speed, approved vaccine projects can submit data to the FDA bit by bit, rather than submitting all the data from a four-phase trial all at once.
Meanwhile, the program is also financially backing efforts to start manufacturing doses while clinical trials are still ongoing. That means if and when those vaccines do get authorized, there will already be a store of doses ready to distribute nationally.