WASHINGTON — Pfizer is "very close" to applying for an emergency use approval for its Covid-19 vaccine after collecting safety data to submit to US regulators, the company's chief executive officer (CEO) said Tuesday (Nov 17), according to a report. 

The pharmaceutical giant announced last week preliminary results from a late-stage clinical trial showing the injections it had co-developed with Germany's BioNTech were more than 90 per cent effective after the second dose.

"We are very close to submitting for an Emergency Use Authorization (EUA)," Dr Albert Bourla told medical news site Stat. "We will announce it as soon as we are doing it."

Pfizer has previously said it expects to contact the US Food and Drug Administration (FDA) to apply for an EUA by the third week of November, meaning the announcement could be days away.

The FDA had imposed a requirement on Covid-19 vaccine makers of having at least two months of follow-up with volunteers after their second dose, taken 28 days after the first, in order to ensure the drugs are safe.

On Monday, Moderna and the US National Institutes for Health announced similar preliminary results from their own trial, finding their vaccine was almost 95 per cent effective. 

Both use mRNA (messenger ribonucleic acid) technology to deliver genetic material to the body that makes human cells create a protein from the virus.

This trains the immune system to be ready to attack if it encounters SARS-CoV-2.

Other vaccines that are in late-stage trials, such as one being developed by Johnson & Johnson and another by Oxford University and AstraZeneca, use modified viruses to deliver genetic material for the same purpose.

No mRNA vaccines have ever been approved, but Dr Anthony Fauci, the United States' top infectious disease scientist said Tuesday the technology had now "established itself."

Dr Bourla told Stat he was relieved that another vaccine was also successful and hoped many more would enter the fray because the global need was so dire.

Moderna has previously said it expects to apply for an EUA by Nov 25.

After the companies apply, the EUAs could follow in a matter of weeks.

Dr Moncef Slaoui, chief of the US government's Operation Warp Speed for vaccine and treatment development, said he expects approval in the first half of December.

Since companies that have been funded by the government have already been manufacturing their doses ahead of approval, Dr Slaoui says there will be enough between Pfizer and Moderna to immunise 20 million Americans in December. AFP