The UK’s National Health Service paved the way for people to receive the second dose of the COVID-19 vaccine made by Pfizer and BioNTech – for a period that companies tested on only a small percentage of patients.
The NHS wrote a letter to hospitals saying that those who are scheduled to receive their second dose after January 4 should be rescheduled from three weeks to 12, with most recipients scheduled for the last week of that period. The move would bring the deadline closer to the newly approved vaccine made by the University of Oxford and the pharmaceutical company AstraZeneca AZN,
Read: The UK now has enough vaccine ‘to cover the entire population’ after AstraZeneca-Oxford COVID-19 vaccine authorization
The NHS said the move would protect the greatest number of people at risk in the shortest period and have the greatest impact on mortality.
Confirmed cases of coronavirus have increased in the past month, with the United Kingdom saying that a new variant of the virus that causes COVID-19 is more easily transmitted. Daily cases increased from 12,330 at the end of November to 50,023 on December 30.
When the UK Medicines and Health Products Regulatory Agency gave emergency approval for the vaccine from the American pharmaceutical company Pfizer PFE,
and its German partner BNTX,
said the dosing interval should be at least three weeks, and based on analyzes that included patients who received their second vaccination within 19 to 42 days after the first vaccination.
Pfizer said the vaccine’s safety and effectiveness were not tested in the new range. “The Phase 3 study by Pfizer and BioNTech for the COVID-19 vaccine was designed to assess the safety and efficacy of the vaccine after a 2-dose schedule, separated by 21 days. The safety and efficacy of the vaccine have not been evaluated in different dosing schedules, as most trial participants received the second dose within the window specified in the study design, ”said the company.
Pfizer also noted that there is no data to show that protection is maintained after 21 days of receiving the first dose.
“While decisions about alternative dosing regimes rest with health authorities, Pfizer believes it is critical that health authorities conduct surveillance efforts on any alternative schemes implemented and to ensure that each recipient receives the maximum possible protection, which it means immunization with two doses of the vaccine, ”said Pfizer. A message left with BioNTech was not returned immediately.
In the information document that pharmaceutical companies provided to the US Food and Drug Administration, they said that about 80% of patients who received the second dose received it within 10 weeks after receiving the first.