We recognize that recommendations on alternative dosing intervals reside with health authorities and may include recommendations due to public health principles. However, as a biopharmaceutical company working in a highly regulated industry, our position is supported by the label and indication agreed upon with Health Canada and informed by data from our Phase 3 study.
Pfizer and BioNTech’s Phase 3 study for the COVID-19 vaccine was designed to evaluate the vaccine’s safety and efficacy following a 2-dose schedule, separated by 21 days. The safety and efficacy of the vaccine has not been evaluated on different dosing schedules as the majority of trial participants received the second dose within the window specified in the study design.
Data from the Phase 3 study demonstrated that, although protection from the vaccine appears to begin as early as 12 days after the first dose, two doses of the vaccine are required to provide the maximum protection against the disease, a vaccine efficacy of 95%. There are no data from this study to demonstrate that protection after the first dose is sustained after 21 days.
We remain committed to our ongoing dialogue with regulators, health authorities and governments, and to our continued data sharing efforts to help inform any public health decisions aimed at defeating this devastating pandemic.