The United Kingdom approved the distribution of the second Covid-19 vaccine on Wednesday. Compared with the Pfizer/BioNTech vaccine, which was similarly approved in the UK on December 2, this newly approved vaccine was developed by the University of Oxford and AstraZeneca, and is cheaper and easier to store.
Officials said the advantages of the Oxford/AstraZeneca vaccine may accelerate vaccination efforts, as the UK is fighting a new, more easily spreading variant of the new virus SARS-CoV-2, which can cause Covid-19.
In a statement, June Raine, chief executive officer of the UK’s Health Regulatory Agency for Drugs and Healthcare Products Regulatory Authority, said: “This approval means that more people can be protected from this virus, and Help save lives.”
According to the New York Times, the UK’s goal is to vaccinate one million people every week and is shifting to a more aggressive vaccination schedule. The country will administer the first dose of vaccine to “as many people as possible,” rather than trying to maintain stockpiles like other countries (including the United States) to ensure everyone gets the second dose.
The high stability and low cost of the Oxford/AstraZeneca vaccine may also bring good news to wealthier countries. If its efficacy is high-if the vaccine is distributed quickly-it can save countless lives. However, some lingering questions about the vaccine’s clinical trial results prevented it from obtaining US approval, and the US is conducting its own trials on the vaccine’s effectiveness.
Why the Oxford/AstraZeneca Covid-19 vaccine is different from the vaccine developed by Pfizer/BioNTech and Moderna
In the United Kingdom, the Oxford/AstraZeneca vaccine has been approved for use in people over 18 years of age. It is usually given at intervals of 4 to 12 weeks between two doses.it Each dose is 3 to 4 dollars and can be stored in a regular refrigerator. In contrast, Moderna and Pfizer/BioNTech vaccines, which have been authorized for emergency use in the United States, cost between US$15 and US$25 per dose and require a refrigerator. Pfizer/BioNTech vaccines in particular need to be refrigerated at minus 70 degrees Celsius (minus 94 degrees Fahrenheit) or lower.
The Oxford/AstraZeneca vaccine also uses a different technology than the Covid-19 vaccine approved so far. Pfizer/BioNTech and Moderna vaccines use molecules called mRNA as their platform to provide instructions for making part of the SARS-CoV-2 virus. The University of Oxford and the University of AstraZeneca used a different innovative method to reprogram another virus to deliver the DNA instructions used to make part of the SARS-CoV-2 virus. Using another virus to package and deliver genetic material helps the Oxford/AstraZeneca vaccine remain stable even at higher temperatures.
However, the University of Oxford and AstraZeneca encountered some problems in their clinical trials, including dose errors, which caused a group of patients to receive less than the full dose for the initial injection. So far, its efficacy seems to be inferior to the Moderna and Pfizer/BioNTech vaccines, although it is well above the 50% vaccine approval threshold set by the US Food and Drug Administration and the European Medicines Agency.
But the actual efficacy value is still unclear, and the efficacy of preventing Covid-19 is between 70% and 90%. Oxford University and AstraZeneca are cautious about certain details of the research.
One of the reasons why the Oxford/AstraZeneca vaccine has been approved in the UK but not in the US is that the UK regulatory agency will review clinical trial data on a rolling basis. FDA hopes to have more complete test data. In the United States, phase 3 clinical trials of the Oxford/AstraZeneca vaccine are still in progress.
At a press conference on December 30, Moncef Slaoui, the scientific director of the US government’s “Quick Action”, said that it may take several months for the United States to approve the vaccine. “If all goes well, we expect to be able to grant readout and emergency use authorization somewhere in early April,” Slaoui said.
But like in the United Kingdom, having another vaccine in the United States, especially one that is cheap and easy to store, will help control the spread of Covid-19. The US government has invested US$1.2 billion in Oxford/AstraZeneca vaccines and has pledged to purchase 300 million doses.