Everything You Need to Know About a Possible Coronavirus Vaccine
Here's a roundup of the latest developments, including where vaccines are in the testing process — and when they might be ready
With COVID-19 continuing to infect people across the globe and no slowdown in sight, hopes are pinned on the dozens of possible vaccines currently in development.
Much like the yearly flu vaccine or the MMR vaccine (measles, mumps and rubella), an effective COVID-19 vaccine would provide some form of immunity and prevent the virus from spreading further. But whether that’s possible — as well as when — remains to be seen.
Here’s what to know about the latest COVID-19 vaccines in development and how they might work.
What is a vaccine?
A vaccine is formulated to prepare the body’s immune system to fight back against a harmful virus or bacteria. A safe version of the virus is introduced to the body through the vaccine so the immune system can learn how to defeat it, typically by forming antibodies.
How many vaccines are in development for COVID-19?
There are 38 different vaccines currently being tested in clinical trials on humans, nine of which are in phase 3 of development, which means they have passed early safety trials and are now part of large clinical trials with thousands of participants. At least 93 more are being tested on animals, according to The New York Times.
Which ones look the most promising?
There are several encouraging candidates around the world, and the U.S. has invested in at least seven companies to help fund their trials. While any vaccine could be available for use in the U.S., the government has to first strike a deal with the vaccine-maker. Two companies the U.S. has funded, Pfizer and Moderna, are deep into phase 3 clinical trials, and look to be the strongest candidates for the U.S.
Pfizer’s vaccine, a collaboration with German company BioNTech and China’s Fosun Pharma, worked well in early trials with only minor side effects like fevers and fatigue, the Times reported. The company is currently one-and-a-half months into a human trial with 30,000 volunteers across the U.S., Argentina, Brazil and Germany. A top executive at Pfizer said the company will likely know by October if the vaccine is effective, and would be able to produce more than 1.3 billion doses by the end of 2021.
Moderna’s vaccine is part of a partnership with the National Institutes of Health, and it began clinical trials in humans in March. Their vaccine also looks promising, and Moderna is now running trials on 30,000 Americans. So far, more than half of the volunteers had side effects, but they were also minor, such as fatigue, chills, headaches and muscle pain, CNN reported.
In both of these vaccine trials, half of the 30,000 participants get a placebo injection of salt water rather than an actual dosage of the vaccine. This enables researchers to see how people with the vaccine react in comparison to those without it.
Another highly promising vaccine, from AstraZeneca and the University of Oxford, began phase 3 trials in Brazil, England, India, South Africa and the U.S. after early trials showed that it raised antibodies against COVID-19 with no severe side effects. On Sept. 8, AstraZeneca had to pause the global trials after one participant developed inflammation. However, this is common practice during vaccine trials while researchers determine if the participant’s reaction is due to the vaccine dose or an unrelated issue. The company said on Sept. 12 that they are resuming the trial in the U.K., but that it would remain on hold in the other countries.
Will the vaccine be safe?
Yes. The large, lengthy clinical trials currently happening are all part of the extensive measures vaccine-makers go through to ensure that their product is completely safe. On Sept. 8, nine of the leading vaccine makers — including Pfizer and Moderna — signed a pledge vowing to follow “high ethical standards” and not rush a vaccine into production before it is proven to work.
The companies said that they will “only submit for approval or emergency use authorization after demonstrating safety and efficacy through a Phase 3 clinical study that is designed and conducted to meet requirements of expert regulatory authorities such as FDA," CNN reported.
The pledge comes after President Donald Trump instructed the CDC to prepare to start distributing a COVID-19 vaccine on Nov. 1, two days before the 2020 election and earlier than experts believed it would be ready.
Pfizer CEO Albert Bourla said on Today that the companies created this pledge due to “increasing public concerns about the processes we are using to develop these vaccines, and even more importantly, the processes that will be used to evaluate these vaccines.” He added that they are focusing on science, and that “the only rival here is the virus.”
Who will get the vaccine first?
The CDC has formed a federal advisory panel to determine who should get the vaccine first. Those in high-risk populations — including health care and other essential workers, the elderly, those in long-term care facilities and people with severe medical conditions — will likely get priority, according to the Washington Post.
Can people who have already had COVID-19 skip the vaccine?
No. While someone who has already recovered from the virus hopefully has antibodies, not everyone does, and experts do not yet know if they provide immunity against getting it again. Plus, it’s not known how long COVID-19 antibodies will last.
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