Pfizer’s COVID-19 vaccine hits 95% efficacy: EUA request to be submitted ‘within days’

By Rachel Arthur

- Last updated on GMT

Pfizer’s vaccine hits 95% efficacy: EUA request to be submitted ‘within days’
Pfizer has revised the efficacy figures for its COVID-19 vaccine candidate – now stating the vaccine is 95% effective – with its Phase 3 study meeting all primary efficacy endpoints.

It has also reached the safety data milestone this week as scheduled: meaning it can provide the required two months of safety data to the US regulator. It says that a request for Emergency Use Authorization will be submitted to the Food and Drug Administration (FDA) ‘within days'.

The Phase 3 study has been concluded with 170 confirmed cases of COVID-19. Of these, 162 cases were seen in the placebo group compared to eight cases in the vaccine group.

The study has recorded 10 cases of severe COVID-19: nine of which occured in the placebo group and one in the vaccine group. 

A vaccine efficacy of 95% for the Pfizer/BioNTech candidate is similar to Moderna's mRNA candidate, which reported 94.5% efficacy​ in its interim analysis (95 cases) on Monday. 

Efficacy consistent across different demographics

Last week, the interim analysis for the Pfizer / BioNTech candidate put the mRNA vaccine at ‘more than 90% efficacy’, based on an analysis of 94 confirmed COVID-19 cases in the study.

The Phase 3 trial had expected to reach the 164 cases required for a primary efficacy analysis in December. However, an increase in the number of COVID-19 cases globally appears to have accelerated the process with the primary efficacy analysis carried out this week with 170 confirmed cases.

This analysis puts the vaccine at 95% efficacy for a two-dose regimen, with efficacy consistent across age, gender, race and ethnicity. In adults over 65 years old, the efficacy was 94%.

Dr. Albert Bourla, Pfizer Chairman and CEO, said: "The study results mark an important step in this historic eight-month journey to bring forward a vaccine capable of helping to end this devastating pandemic. We continue to move at the speed of science to compile all the data collected thus far and share with regulators around the world."

Ugur Sahin, M.D., CEO and Co-founder of BioNTech, added: "We are grateful that the first global trial to reach the final efficacy analysis mark indicates that a high rate of protection against COVID-19 can be achieved very fast after the first 30 µg dose, underscoring the power of BNT162 in providing early protection.

"These achievements highlight the potential of mRNA as a new drug class. Our objective from the very beginning was to design and develop a vaccine that would generate rapid and potent protection against COVID-19 with a benign tolerability profile across all ages.

"We believe we have achieved this with our vaccine candidate BNT162b2 in all age groups studied so far and look forward to sharing further details with the regulatory authorities.

"I want to thank all the devoted women and men who contributed to this historically unprecedented achievement. We will continue to work with our partners and governments around the world to prepare for global distribution in 2020 and beyond.”

Study diversity

  • 42% of global participants / 30% of US participants have racially & ethnically diverse backgrounds
  • 41% of global / 45% of US participants are 56-85 years old
  • Further diversity data here

The Phase 3 trial has enrolled 43,661 participants to date.

Of these, the vast majority (44,135) have already received the second dose of the vaccine.

The study is being carried out across 150 trial sites in the US, Germany, Turkey, South Africa, Brazil and Argentina. 

The trial will continue to collect efficacy and safety data for two years. 

Safety data

As scheduled, Pfizer now has two months of safety data, which is required in order to submit a EUA request to the FDA. 

The Data Monitoring Committee has not reported any serious safety concerns related to the vaccine. A review of unblinded reactogenicity data from the final analysis which consisted of a randomized subset of at least 8,000 participants 18 years and older in the phase 2/3 study demonstrates that the vaccine was 'well tolerated, with most solicited adverse events resolving shortly after vaccination'.

"The only Grade 3 (severe) solicited adverse events greater than or equal to 2% in frequency after the first or second dose was fatigue at 3.8% and headache at 2.0% following dose 2,"​ states Pfizer. "Consistent with earlier shared results, older adults tended to report fewer and milder solicited adverse events following vaccination."

Along with the safety data, Pfizer will also need to submit the efficacy data alongside manufacturing data relating to the quality and consistency of the vaccine.

Data will also be submitted to other regulatory agencies around the world: although a timeframe for this has not been given. In October, the European Medicines Agency started a rolling review of non-clincial and earlier clinical data for the vaccine. 

Pfizer and BioNTech expect to produce up to 50 million vaccine doses worldwide in 2020. By the end of 2021, they plan to produce up to 1.3 billion doses.

Four of Pfizer’s facilities are part of the manufacturing and supply chain; situated in St. Louis, MO; Andover, MA; and Kalamazoo, MI in the US; alongside Puurs in Belgium. Meanwhile, BioNTech will leverage its German sites for global supply.

Related topics Bio developments COVID-19

Related news

Show more