About Our Landmark Trial

The primary endpoints of the COVID-19 vaccine study were safety and to evaluate the efficacy of the vaccine candidate in preventing COVID-19 disease in participants who had not been infected with the SARS-CoV-2 virus before they received the vaccine, and to evaluate potential prevention of COVID-19 disease in participants who had prior exposure to SARS-CoV-2.

The primary efficacy endpoints evaluated confirmed COVID-19 cases occurring 7 days or more after the second dose. The primary analysis also included, with the approval of the FDA, secondary endpoints evaluating efficacy based on COVID-19 cases occurring 14 days after the second dose. Pfizer and BioNTech believe that the addition of these secondary endpoints enabled assessment of data across all COVID-19 vaccine studies and allowed for cross-trial learnings and comparisons between various vaccine platforms.

Pfizer also plans to continue to evaluate safety and long-term outcomes data from participants for a full two years.

There are many different types of clinical studies. Randomized, placebo-controlled studies are considered the “gold standard” in clinical research, because they eliminate potential biases when interpreting data.

One reason we chose this type of study to test our vaccine candidate was that it helped us understand whether people who received the vaccine candidate were better protected from COVID-19 disease than people who do not receive it.

We enrolled 46,331 people in the trial, with the majority of participants ranging from ages 16-56. Additional trial populations included people as young as 12 years old and people with chronic, stable human immunodeficiency virus (HIV), Hepatitis C virus (HCV), or Hepatitis B virus (HBV) infections. We believe that doing so enabled more individuals who were at risk of COVID-19 disease to have the opportunity to participate in the study. As with the vaccine candidates we test in adult populations, we followed a careful, stepwise approach as we moved down to younger age groups.

In March 2021, Pfizer and BioNTech announced positive topline results of the pivotal COVID-19 vaccine study in 2,260 adolescents ages 12-15. All participants in the trial will continue to be monitored for long-term protection and safety for an additional two years after their second dose.

On April 9, 2021, the Companies have submitted these data to the FDA and requested an amendment to the Emergency Use Authorization of BNT162b2 to expand use in adolescents 12-15 years of age.

Even though we moved with extraordinary speed, preservation of high quality and safety standards was critically important throughout development. We took all of the regulatory and operational steps that we would normally take for all of our vaccine trials, maintaining the highest standards in our development process. This required enormous mobilization of Pfizer and BioNTech resources upfront at a scale never seen before. We also worked closely with regulatory agencies, providing near real-time data and receiving review and advice more quickly than ever before, to support the development of this potential vaccine as quickly as possible.