Pfizer and BioNTech’s coronavirus vaccine appears to protect 94% of adults over 65 years of age.
More data published from their current phase III study show that the vaccine works equally well in people of all ages, races and ethnicities.
The companies say they will now apply for an emergency permit for use in the United States.
The findings are based on two doses given to more than 41,000 people worldwide.
Last week, Pfizer and BioNTech released preliminary data showing that the vaccine offers 90% protection against Covid-19 and no safety concerns.
This was followed by impressive data on another vaccine made by the American company Moderna, which assumes nearly 95% protection.
The November 18 data from Pfizer and BioNTech, based on data from last week, showed that the vaccine was 95% effective based on 170 Covid-19 cases developed in volunteers.
Only eight were in the group that received the vaccine, suggesting that it offers good protection. The remaining cases were in the placebo group, which received a fictitious stroke.
Modern Vaccine shows nearly 95% protection against Covid-19 Coronavirus: Pfizer vaccine offers 90% protection
The researchers said the data further encouraged the news.
Although full test data have not yet been released, companies say there are no serious safety concerns.
However, they noticed headaches and fatigue in about 2% of the volunteers who received the vaccine, although older people appeared to experience minimal side effects.
There is also evidence that the vaccine protects against severe Covid – but this is based on only 10 cases.
It is not yet clear how long protection against the vaccine lasts and whether it stops people from transmitting the virus.
In the process, 42% of all participants were of different ethnic backgrounds, and 41% were between 56 and 85 years old.
The study, which tested people at 150 sites in the United States, Germany, Turkey, South Africa, Brazil and Argentina, will collect data on the safety and efficacy of the vaccine for another two years.
Pfizer and BioNTech expect to produce up to 50 million doses of the vaccine this year and up to 1.3 billion doses by the end of 2021.
Hundreds of vaccines are being developed around the world and about a dozen in the final stages of testing, known as phase three.
The first two, which show any results – made by Pfizer-BioNTech and Moderna – both use an experimental approach called mRNA, which involves injecting part of the genetic code of the virus into the body to train the immune system.
The body then produces antibodies and T cells to fight the coronavirus.
Russia’s Sputnik vaccine also published early phase III data based on fewer volunteers and Covid cases.
There are some logistical challenges with mRNA vaccines, namely the need to store them at low temperatures.
The Pfizer vaccine should be stored at about minus 80 ° C, although it can be stored in a refrigerator for five days.
Moderna vaccine should be stored at minus 20 ° C for up to six months and stored in a standard refrigerator for up to one month.