Early clinical trials of a Covid-19 vaccine that is among those currently in late-stage testing have shown favorable responses among participants in terms of antibody and immune cell responses.
Mainz, Germany-based BioNTech and New York-based Pfizer said late Thursday afternoon that among U.S. Phase I student participants who received the BNT162b2 vaccine at 30 micrograms, participants aged 18-55 showed average concentrations of antibodies against SARS-CoV. 2 at 3.8 times those of recovering patients seven days after the second dose, whereas those aged 65-85 years showed 1.6 times higher.
Shares of BioNTech rose 12.1% on the Nasdaq when markets opened Friday. Shares of Pfizer were mostly flat on the New York Stock Exchange.
Adverse events among those receiving BNT162b2 included fever, fatigue, and chills, but no serious effects, and the vaccine was described as having a favorable tolerability profile compared with a similar vaccine candidate, BNT162b1.
BNT162b2 was selected at the end of last month from multiple messenger RNA vaccines against SARS-CoV-2 and is currently being developed in a Phase II / III study that will enroll approximately 30,000 participants. The companies said that since Thursday, more than 11,000 participants had already been dosed in the trial, which includes 113 sites in the US, Argentina and Brazil.
“The entirety of the clinical and preclinical data informed Pfizer and BioNTech’s decision to select BNT162b2 as the lead candidate to proceed in pivotal trials,” Pfizer head of fax research and development Kathrin Jansen said in a statement. “We are particularly pleased to present these early data showing the promising safety and immunogenicity profile of our vaccine candidate from the US trial, and we look forward to sharing T-cell immune response data from the German trial in the whole future. “
However, it remains to be seen whether each Covid-19 vaccine candidate offers long-term protection, so that annual vaccinations would be sufficient to protect against infection. Other late-stage vaccines include Moderna’s mRNA-1273, also a messenger RNA vaccine, and AZD1222, licensed by AstraZeneca from the University of Oxford in the United Kingdom.
An example of a vaccine being marketed early earlier this month, when authorities in Russia claimed that a vaccine they had developed was ready for market despite the lack of Phase III data, let alone data on long-term effectiveness.
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