In the past few weeks, the world has gotten some very encouraging and hopeful news on several upcoming COVID-19 vaccines.
Many different institutions around the world have been working on potential vaccines to prevent or stop the spread of SARS-CoV-2 since the emergence and international spread of the virus in early 2020. Of all the candidates, many progressed rapidly through initial research stages and clinical trials, with multiple in stage 3 clinical trials right now.
Recently, both Pfizer and Moderna have announced that preliminary results from their clinical trials put both of their candidates at approximately 95% efficacy for prevention of contracting COVID-19. This is excellent news as the northern hemisphere prepares to hunker down for the winter season. In the past few days, we have also heard that Astra-Zeneca’s vaccine candidate has shown promising results, including a strong response in older adults, although no data has been made publicly available yet.
More details on Pfizer's and Moderna's vaccine candidates is as follows:
Pfizer and BioNTech
Pfizer and BioNTech released new results from the Phase 3 Clinical trial of their vaccine candidate BNT162b2 on November 9th, 2020, that suggested the candidate was more than 90% effective. Even more recently, on November 18, 2020, the companies released final results of their study indicating that the vaccine candidate is actually 95% effective. These numbers are based off of 170 of the participants who contracted COVID-19 over the course of the trial, with 162 of them in the placebo group, and just 8 cases in the experimental group. These results still have yet to be properly and thoroughly peer-reviewed, but are promising enough that Pfizer and BioNTech hope to apply for emergency use authorization from the US FDA to hopefully start vaccinating millions of people by the end of the year.
In between press releases from Pfizer and BioNTech, on November 16th, 2020, Moderna also released new results from the clinical trial of their vaccine candidate, mRNA-1273, indicating that it was 94.5% effective. These results also still need to be peer reviewed, but are based off of 95 cases of COVID-19, where 90 of the cases were in the placebo group, and only 5 cases were in the vaccinated group. Both Pfizer & BioNTech’s and Moderna’s vaccine candidates are mRNA vaccines, which have not been used in humans before, but if they are successful, could be very promising for future vaccine development. Moderna is also planning to apply to the FDA for emergency use authorization in the coming days.
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