Anti-Covid Vaccine: BioNTech Warns About Dose Spacing
To accelerate the fight against coronavirus, some countries have chosen to space the administration of the two doses of the Pfizer / BioNTech vaccine more than the recommended 21 days. BioNTech Lab cautions.
Several European countries, notably the UK, have adopted a strategy that some might describe as reckless, if not risky. It consists of massively immunizing the population, using the first dose of Pfizer / BioNTech or Moderna anti-Covid vaccines, and delaying the administration of the second dose.
Therefore, the British have planned to postpone the injection of the second dose of the vaccine until 12 weeks after the first. Denmark plans to use two doses of the vaccine with an interval of up to six weeks.
However, "the effectiveness and safety of the vaccine have not been evaluated for other dosage schedules", other than that of two injections spaced 21 days apart, as applied during the clinical trial, detailed the German biotechnology company BioNTech. "Although there is data that shows that there is partial protection as early as 12 days after the first dose, there is no data that shows that protection remains in place beyond 21 days," he added.
"We believe that a second injection is necessary to provide maximum protection against the disease," added the laboratory, which specializes in messenger RNA. This indicates being in "continuous dialogue" with the health authorities of countries that have opted for "alternative dosage regimens".
According to a document recently consulted by AFP, Germany, which is experiencing a significant epidemic rebound, is also studying the possibility of a longer delay between two doses of vaccine.
Very debatable on a strictly scientific level, such a strategy somehow favors a weaker immune response but in more people, rather than a maximal immune response for a smaller number of individuals.
Published in the New England Journal of Medicine on Dec. 31, the Pfizer / BioNTech Vaccine Efficacy Study reports 52% vaccine efficacy after a single dose, compared to 95% when both doses are given. with an interval of 21 days.
It should also be noted that the idea of mixing several different vaccines, for example receiving a first dose of the Pfizer / BioNTech vaccine and a second dose of the AstraZeneca vaccine, is even more debated. Because this combination has not been studied or evaluated on a scientific and medical level.