The Covid-19 vaccine candidate being developed by US pharmaceutical company Pfizer and German biotechnology company BioNTech has yielded positive data in early tests, according to data released by the companies.
The companies announced these preliminary findings on Wednesday in a pre-print paper that shows participants in a Phase 1/2 study of the vaccine, called BNT162b1, responded to the immunization and it was found to be well tolerated. The Phase 1/2 study is ongoing. The data has not yet been published in a peer-reviewed medical journal.
"These clinical findings for the BNT162b1 RNA-based vaccine candidate are encouraging and strongly support accelerated clinical development and at-risk manufacturing to maximize the opportunity for the rapid production of a SARS-CoV-2 vaccine to prevent COVID-19 disease," the researchers wrote in the pre-print paper, which was sponsored by BioNTech and designed by Pfizer.
How the study was conducted: For the initial study, 45 participants ages 18 to 55 were randomly assigned to either receive a certain dose of the vaccine or placebo.
Twelve participants received two 10 microgram doses 21 days apart; 12 received two 30 microgram doses 21 days apart; 12 received a single 100 microgram dose on day one; and nine received placebo, according to the study.
In the seven days following injection of the vaccine, some participants who received a dose reported pain in the injection site, fever or sleep disturbances, but "no serious adverse events were reported," according to the paper.
Early results of the study: The researchers found that the vaccine generated antibodies against the coronavirus in all of the participants by 28 days after receiving a single injection of 100 micrograms or seven days after receiving a second dose of either 10 or 30 micrograms.
"These preliminary data are encouraging, showing that BNT162b1 which exploits RBD SARS-CoV-2 as a target antigen is able to produce neutralizing antibody responses in humans at or above the levels observed in convalescent sera – and that it does so at relatively low dose levels. We look forward to providing further data updates on BNT162b1," Dr. Ugur Sahin, CEO and co-founder of BioNTech, said in a company press release on Wednesday.
Pfizer and BioNTech announced on Wednesday that this preliminary data will help them determine a dose level for the vaccine then select which of their multiple vaccine candidates to progress to a larger-scale global Phase 2/3 study, possibly beginning as early as this month.
According to the World Health Organization, there are 17 coronavirus candidate vaccines in clinical evaluation globally.