Pfizer’s COVID-19 vaccine protection lasts for at least six months

Published April 5, 2021, 10:13 AM

by Jaleen Ramos

Pfizer and BioNTech announced that results from the ongoing phase three trial of their vaccine showed its protection against the virus lasts for at least six months.

Phials of the Pfizer/BioNTech Covid-19 vaccine are pictured at the Palais des Sports venue in Lyon, hosting a Covid-19 vaccination centre, on March 29, 2021 as France faces a new wave of infections to the novel coronavirus. (Photo by JEAN-PHILIPPE KSIAZEK / AFP)

The vaccine remains 91.3 percent  effective against the coronavirus disease (COVID-19), measured seven days through six months after the second dose, the companies said.

The vaccine was also found to be fully effective against the B.1.351 variant, which is now the dominant strain in South Africa.

“The high vaccine efficacy observed through up to six months following a second dose and against the variant prevalent in South Africa provides further confidence in our vaccine’s overall effectiveness,” said Albert Bourla, Chairman and Chief Executive Officer of Pfizer in a statement. 

“It is an important step to further confirm the strong efficacy and good safety data we have seen so far, especially in a longer-term follow-up,” said Ugur Sahin, CEO and Co-founder of BioNTech. 

“These data also provide the first clinical results that a vaccine can effectively protect against currently circulating variants, a critical factor to reach herd immunity and end this pandemic for the global population.”

Overall, the vaccine was 91.3 percent effective against COVID-19 in the analysis of 46,307 trial participants across several countries.

From the analysis of 927 confirmed symptomatic cases of COVID-19 in the trial, 850 cases were in the placebo group and 77 cases were in the vaccinated group.

“Thirty-two cases of severe disease, as defined by the CDC, were observed in the placebo group versus none in the BNT162b2 vaccinated group, indicating that the vaccine was 100 percent efficacious in this analysis against severe disease by the CDC definition. Twenty-one cases, as defined by the FDA, were observed in the placebo group versus one case in the BNT162b2 vaccinated group, indicating 95.3 percent efficacy by the FDA definition.”

Efficacy was generally consistent across age, gender, race, and ethnicity demographics, and across participants with a variety of underlying conditions, the companies added.

The Pfizer-BioNTech COVID-19 vaccine has been listed for emergency use for active immunization to prevent COVID-19 in individuals 16 years of age and older.

Global deaths from COVID-19 have already reached more than two million since the pandemic began last year. (With a report from Agence France-Presse)