This animated video explains how Pfizer and Moderna's genetic vaccine works against COVID-19.
Of 196 COVID-19 cases so far in its huge U.S. study, 185 were trial participants who received the placebo and 11 who got the real vaccine. The only people who got severely ill — 30 participants, including one who died — had received dummy shots, said Dr. Tal Zaks, the Cambridge, Massachusetts, company's chief medical officer.
When he learned the results, “I allowed myself to cry for the first time,” Zaks told The Associated Press. “We have already, just in the trial, have already saved lives. Just imagine the impact then multiplied to the people who can get this vaccine.”
Moderna said the shots’ effectiveness and a good safety record so far — with only temporary, flu-like side effects — mean they meet requirements set by the U.S. Food and Drug Administration for emergency use before the final-stage testing is complete. The European Medicines Agency, Europe’s version of FDA, has signaled it also is open to faster, emergency clearance.
WHAT COMES NEXT
The FDA has pledged that before it decides to roll out any COVID-19 vaccines, its scientific advisers will publicly debate whether there’s enough evidence behind each candidate.
First up on Dec. 10, Pfizer and BioNTech will present data suggesting their vaccine candidate is 95% effective. Moderna said its turn at this “science court” is expected exactly a week later, on Dec. 17.
RATIONING INITIAL DOSES
If the FDA allows emergency use, Moderna expects to have 20 million doses ready for the U.S. by year’s end. Recipients will need two doses, so that’s enough for 10 million people.
Pfizer expects to have 50 million doses globally in December. Half of them — or enough for 12.5 million people — are earmarked for the U.S.
This week, a different panel of U.S. experts, established by the Centers for Disease Control and Prevention, will meet to decide how initial supplies will be given out. They're expected to reserve scarce first doses for health care workers and, if the shots work well enough in the frail elderly, for residents of long-term care facilities. As more vaccine gradually becomes available in coming months, other essential workers and people at highest risk from the coronavirus would get in line. But enough for the general population isn't expected until at least spring.
Outside the U.S., Zaks said significant supplies from Moderna would be available later, “in the first quarter” of next year.
“Obviously we are doing everything in our power to increase the capacity and accelerate the timelines,” he said.
Both Moderna's and Pfizer's vaccines are made with the same technology, using a piece of genetic code for the “spike” protein that studs the virus. That messenger RNA, or mRNA, instructs the body to make some harmless spike protein, training immune cells to recognize it if the real virus eventually comes along.
ASTRAZENECA CONFUSION
AstraZeneca last week announced confusing early results of its vaccine candidate from research in Britain and Brazil
That vaccine appears 62% effective when tested as originally intended, with recipients given two full doses. But because of a manufacturing error, a small number of volunteers got a lower first dose — and AstraZeneca said in that group, the vaccine appeared to be 90% effective.
Experts say it’s unclear why the lower-dose approach would work better and that it may just be a statistical quirk.
A larger U.S. study of the AstraZeneca candidate still is underway that should eventually give the FDA a better picture of how well it works. The FDA has said any COVID-19 vaccine would have to be at least 50% effective.
Meanwhile Britain’s government will have to decide whether its U.K. data is sufficient for an early rollout there.
STILL IN THE PIPELINE
Johnson & Johnson also is in final-stage testing in the U.S. and several other countries to see if its vaccine candidate could work with just one dose.
Both the J&J and AstraZeneca vaccines work by using harmless cold viruses to carry the spike protein gene into the body and prime the immune system.
The different technologies have ramifications for how easily different vaccines could be distributed globally. The AstraZeneca shots won't require freezer storage like the Pfizer and Moderna vaccines.
Candidates made with still other technologies are in late-stage testing, too. Another U.S. company, Novavax Inc., announced Monday that it has finished enrolling 15,000 people in a late-stage study in Britain and plans to begin recruiting even more volunteers for final testing in the U.S. and Mexico “in the coming weeks.”
Vaccines made by three Chinese companies and a Russian candidate also are being tested in thousands of people in countries around the world.
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November 30, 2020 at 07:07PM
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Moderna asking US, European regulators to OK its virus shots - KSTP
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