Pfizer and its partner BioNTech are on Friday filing for emergency authorisation in the US of their Covid-19 vaccine.
It will be the job of the US Food and Drug Administration (FDA) to decide if the vaccine is safe to roll out.
It is not clear how long the FDA will take to study the data. However, the US government expects to approve the vaccine in the first half of December.
Data from an advanced trial showed the vaccine protects 94% of adults over 65.
The trial involved 41,000 people worldwide. Half were given the vaccine, and half a placebo.
The UK has pre-ordered 40 million doses and should get 10 million by the end of the year.
So when could we expect vaccinations?
If FDA authorisation does come in the first half of next month, Pfizer and BioNTech will “be ready to distribute the vaccine candidate within hours”, the two companies said.
This would be remarkably quick for vaccine development – within 10 months of detailing the genetic code. The average wait for approval in the US is nearer eight years.
Pfizer CEO Albert Bourla said on Thursday that the filing for emergency use was a “milestone in our journey to deliver a Covid-19 vaccine to the world”.
Initial doses would be scarce, though, and the Centers for Disease Control and Prevention (CDCP) will decide who is first in line.
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