After many months of waiting, today we have some good news about COVID-19 vaccination. Two leading companies who are working on COVID-19 vaccines- Pfizer Inc and BioNTech SE announced that their mRNA-based vaccine candidate BNT162b2 against COVID-19 (SARS-CoV-2) has demonstrated evidence of efficacy against COVID-19, in participants without prior evidence of COVID-19 infection. The report is based on the first interim efficacy analysis from the Phase 3 trial.
All the vaccines that are being developed are focusing on the protein spike of the virus and there were some theoretical concerns about this target. Today it has been proven that targeting the protein spike is the right approach. This new vaccine candidate targets the protein spike of the virus. The spike protein is the knobby protrusion on Covid-19 virus that helps virus to attach to and invade cells during infection.
Dr. Albert Bourla, Pfizer Chairman and CEO said “Today is a great day for science and humanity. The first set of results from our Phase 3 COVID-19 vaccine trial provides the initial evidence of our vaccine’s ability to prevent COVID-19,”
Pfizer Inc in their website announced the news with following crucial details:
- Vaccine candidate was found to be more than 90% effective in preventing COVID-19 in participants without evidence of prior SARS-CoV-2 infection in the first interim efficacy analysis
- Analysis evaluated 94 confirmed cases of COVID-19 in trial participants
- Study enrolled 43,538 participants, with 42% having diverse backgrounds, and no serious safety concerns have been observed; Safety and additional efficacy data continue to be collected
- Submission for Emergency Use Authorization (EUA) to the U.S. Food and Drug Administration (FDA) planned for soon after the required safety milestone is achieved, which is currently expected to occur in the third week of November
- Clinical trial to continue through to final analysis at 164 confirmed cases in order to collect further data and characterize the vaccine candidate’s performance against other study endpoints
The phase 3 trial was beginning on July 27th with enrollment of 43,538 participants to date and 38955 participants received the second dose of the candidate vaccine as of this week. Amongst the participant 42% are global and 30% are US volunteers with both ethnically and racially diverse backgrounds.
The study will evaluate the potential for the vaccine candidate to give protection for those who had prior exposure to Covid-19 as well as for those who are severely infected with the disease. The final analysis will also include new secondary endpoints evaluating efficacy based on cases accruing 14 days after the second dose. This will help to align data across all studies of Covid-19 vaccine.
In June, FDA informed manufacturers that it would accept a vaccine that reduces the risk of symptomatic Covid by 50%. Reason for this is, many of the vaccines that target pathogens that invade respiratory system do not generate proper immune responses.
Both companies are accumulating safety data for the second dose of the vaccine candidate as per FDA guidelines. Both companies have reported that there is no safety concerns for this vaccine candidate. In addition, all the participants will be monitored for long-term protection as well as safety for two years after the second dose of vaccine.
Companies are expected to produce up to 50 million vaccine doses in 2020 and up to 1.3 billion doses in 2021 globally.
Who will be getting new vaccine first?
According to the sources, groups that are at high risk of infection or more vulnerable to Covid-19 viruses are likely to get priority. This might include health care workers, older adults and those who have preexisting conditions like diabetes.
For further reading:
image credit: https://www.flickr.com/photos/30478819@N08/50308119421 (Cc by 2.0)
Author: Sumana Rao | Posted on: November 10, 2020