The UK National Health Service has pushed back the window for people to receive the second dose of COVID-19 vaccine developed by Pfizer and BioNTech – at a time when companies have tested only a small percentage of patients .
The NHS has written a letter to hospitals saying that those scheduled to receive the second dose after 4 January should be rescheduled from three to 12 weeks, with most beneficiaries being booked in the last week of that time. The measure would bring the window closer to the time period for the vaccine approved only by Oxford University and the pharmaceutical company AstraZeneca AZN,
Read: The UK now has enough vaccine “to cover the entire population” after the AstraZeneca – Oxford COVID-19 vaccine was approved
The NHS said the measure would protect the largest number of people at risk in the shortest time and have the greatest impact on mortality.
Confirmed cases of coronavirus have increased in the last month, with the UK claiming that a new variant of the virus that causes COVID-19 is more easily transmitted. Daily cases rose from 12,330 at the end of November to 50,023 on December 30.
When the UK Medicines and Medicines Regulatory Agency gave emergency approval to the vaccine from the US drug company Pfizer PFE,
and its German partner BNTX,
said the dose interval should be at least three weeks and is based on tests that included patients who received the second vaccination within 19 to 42 days of the first vaccination.
Pfizer said the safety and effectiveness of the vaccine have not been tested in the new range. The Pfizer and BioNTech Phase 3 study for the COVID-19 vaccine was designed to evaluate the safety and efficacy of the vaccine following a 2-day, 21-day schedule. The safety and efficacy of the vaccine were not evaluated on different dosing schedules, as most study participants received the second dose in the window specified in the study design, “the company said.
Pfizer also noted that there is no evidence that protection is sustained 21 days after receiving the first dose.
“While decisions on alternative dosing regimes belong to health authorities, Pfizer considers it essential that health authorities make efforts to monitor any alternative programs implemented and to ensure that each beneficiary is given the maximum possible protection. means immunization with two doses of vaccine. ” said Pfizer. A message left at BioNTech was not returned immediately.
In the information document provided by the drug companies to the US Food and Drug Administration, they said that about 80% of patients who received the second dose were given it within 10 weeks of receiving the first dose.