Pfizer Gave An Exciting Update About Its COVID-19 Vaccine’s Effectiveness

On Nov. 9, Pfizer and BioNTech announced their COVID-19 vaccine seems to be 90% effective, per analysis by an independent panel of experts — a major milestone in the fight against the pandemic. On Nov. 18, further data showed the vaccine appears to be 95% effective, and works in people of all ages and ethnic backgrounds, per the BBC.

The vaccine — one of 10 being tested around the world — was studied in 43,500 people, with no reported safety concerns. Participants received either an active or a placebo shot. Two doses of the vaccine, three weeks apart, protects against COVID, Pfizer announced.

By Nov. 18, 170 volunteers in the trial were confirmed to have COVID-19. Only eight of them had the vaccine, according to the BBC; the rest had placebo doses. That's how scientists know the vaccine is 95% effective. Of the 170 cases of COVID-19, nine people had severe symptoms. Only one of the nine had the vaccine, according to Science.

The study participants were only tested for coronavirus if they developed symptoms, according to the AP. The researchers don't know yet if vaccinated people might still get COVID-19, but be asymptomatic.

The vaccine works by injecting part of COVID-19’s genetic code into your body, training your immune system to recognize and fight against it. Pfizer has reported that people in the trial reported "mild to moderate" side effects, including chills, headaches, and fevers.

To allow Pfizer to apply for emergency use authorization, the FDA needed two full months of data showing at least 50% effectiveness. Pfizer announced that they’d reached that point on Nov. 18 and would apply soon.

The trial is also looking at whether their vaccine protects people who've had COVID before. The CEO of BioNTech said he hopes the data will reveal the vaccine might last a year.

If the tests are successful and the FDA mandates the vaccine, Pfizer will produce 600 million doses for the U.S., though only around 50 million will be ready this year. Dr. Anthony Fauci, director of the National Institute of Allergy and Infectious Diseases, told CNN people might be able to get vaccinated by late December.

Beyond Pfizer, drug companies including AstraZeneca and Moderna are all doing late-stage testing on vaccines. Moderna's is also 94.5% effective, the company announced Monday. Pfizer is one of the few not to have used federal money to develop it as part of Operation Warp Speed, The New York Times says.

If the Pfizer vaccine is authorized, it will likely be reserved for healthcare professionals and emergency workers first. The rest of us might not get a dose until next year.