Efficacy, side effects … What we know about Pfizer and Astrazeneca vaccines

The two competitors unveiled the results of their studies this week. Le Figaro sifted through them.

After several weeks of waiting, the efficacy and safety data of the most advanced vaccines against Covid-19 are gradually being made public. These so-called results of “phase 3», Which involve tens of thousands of volunteers, provide a more precise idea of ​​the efficacy of the vaccine and the potential adverse effects.

It is on this basis that the health authorities decide whether or not to authorize them. You will find below all the necessary information, vaccine by vaccine on all these data, as they will be published, either by the health authorities or in international scientific journals.

Pfizer / BioNTech (RNA vaccine)


  • The vaccine developed by Pfizer and BioNTech is a RNA vaccine. It consists of injecting into our body a fragment of virus genetic material, which contains the assembly instructions for a viral protein. Thanks to this genetic code, our own cells will make this protein. These small virus elements – harmless as they are – will then serve as training targets to our immune system. In practice, the viral protein made is the spicule located on the surface of Sars-Cov-2, a kind of key that allows the virus to enter human cells. There is no no risk that this fragment integrates into or modifies our own DNA .
  • This vaccine should be stored between – 80 ° C and – 60 ° C degrees, which makes its deployment quite complex.
  • The vaccine is 95% efficient at this time, with limited side effects.
  • The United Kingdom, the Canada, the Bahrain and the United States authorized it. The UK is the first country to launch its vaccination campaign, December 8.
  • The European Commission pre-ordered 200 million doses, as well as 200 million optional doses.
  • The phase 3 data was the subject of a briefing note from the US drug agency, the FDA, and a scientific publication in the New England Journal of Medicine .


Near 44,000 people over 16 years of age took part in Phase 3 trials in six countries: the United States, Argentina, Brazil, Germany, South Africa and Turkey. They were randomly divided into two groups: the first received of them

This article is for subscribers only. You have 92% left to discover.

Subscribe: 1 € the first month

Can be canceled at any time

Already subscribed? Log in


Leave a Reply

Your email address will not be published. Required fields are marked *