It was a source of great comfort and hope to many people around the world last week that a Covid-19 vaccine, jointly developed by pharmaceutical company Pfizer and technology company BioNTech, was said to be ‘90% effective.’ The vaccine is undergoing Phase 3 trials at the moment. It was even a further beacon of hope when a second company, Moderna, a firm in the United States, made a press release stating that they had also created a vaccination against Covid-19 that is 94.5% effective. As we go to print, Pfizer and BioNTech have updated their clinical trials and said that their vaccine is now expected to be 95% effective in the battle against Covid-19 as their trials are brought to an end.
Dr. Anne Moore, a Senior Lecturer in Biochemistry and Cell Biology at UCC joined Bryan Dobson on RTÉ Radio One to discuss the story as it broke last week. Dr. Moore explained what is involved during Phase 3 of vaccine trials, “The Phase 3 trial is where we really look to see if the vaccine can work, as in it protects people against infection or disease”, she said. “We look at that in thousands of people so see if it really does provide protection and we also look at the safety signals in such a big population of people. This trial took place in over 40,000 people, both those who got the vaccine and those who got a placebo”, she said.
Pfizer presented their results, also known as interim analysis, to the Food and Drug Administration (FDA) earlier this week. ” Pfizer will more than likely aim to be granted ‘an emergency use authorisation’ for the vaccine. They will be granted this licence, provided there are no major health or safety signals – and so far, there appears to be no adverse effects, Dr. Mooney explained. “If there aren’t [adverse effects] for a further two months, then there will be a vaccine licence for Covid-19 by the end of the year. It’s a really positive breakthrough.” The Pfizer vaccine has been shown to produce both an antibody and T-cell response in the body to fight coronavirus. Pfizer and BioNTech expect to be able to produce up to 50 million vaccine doses globally in 2020 and up to 1.3 billion in 2021.
According to the press release issued by Pfizer, the efficacy of the vaccine developed was consistent across age and ethnicity demographics, and that there no major side effects, a sign that the immunisation could be employed broadly around the world. Other immunologists and biochemists have exercised a welcome but cautious reaction to the press release issued by Pfizer. The Irish Times have exercised caution at the development, with Dr. Muiris Houston raised questions that haven’t been addressed; such as how long the protective effect of the vaccine last and will the vaccine work equally well in everyone and will it prevent transmission of the virus?
Some practical issues with the Pfizer vaccine require storage at a temperature below minus seventy degrees Celsius. This is a global shipping challenge; at a local level, it means the vaccine will not be available from local medical practices. According to Dr. Anne Moore, of UCC, “there are at least half a dozen other vaccines which are on the same track so hopefully, we will have multiple vaccines which will be licensed. The fact that one vaccine will provide very early stage protection gives us a lot of optimism that other vaccines will be effective.”