An ongoing trial of Pfizer’s COVID-19 vaccine has confirmed that it is “highly effective” against COVID-19 (as well as variants of the virus) for half a year after the second dose.
On Thursday, the companies said data from more than 12,000 vaccinated participants showed that the vaccine was still protective six months later, demonstrating a “favorable safety and tolerability profile.”
“These data confirm the favorable efficacy and safety profile of our vaccine and position us to submit a Biologics License Application to the U.S. FDA,” said Albert Bourla, Pfizer’s Chairman and CEO, in a press release. “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.”
The study is ongoing, and those involved will continue to be evaluated after another six months have passed. For now, Pfizer and BioNTech have confirmed that the vaccine remains more than 91 percent effective against COVID-19 with any symptoms for six months.
Protective against variants
The vaccine developed by Pfizer and BioNTech also appeared to protect vaccine recipients against the South African coronavirus strain, B.1.351 -- a variant that was previously believed to evade the protection of vaccines.
"The vaccine was 100% effective against severe disease as defined by the U.S. Centers for Disease Control and Prevention (CDC), and 95.3% effective against severe COVID-19 as defined by the U.S. Food and Drug Administration (FDA)," Pfizer and BioNTech said.
“In South Africa, where the B.1.351 lineage is prevalent and 800 participants were enrolled, nine cases of COVID-19 were observed, all in the placebo group, indicating vaccine efficacy of 100%," the company said.
Pfizer’s CEO said the promising data positions the company to submit a Biologics License Application (BLA), or an application for full approval, to the FDA.
"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,” Bourla said.