AstraZeneca should still know by year-end whether its experimental vaccine protects people against coronavirus, as long as it is cleared to resume trials soon, its chief executive said on Thursday amid doubts over its rollout. Governments desperate to put an end to the COVID-19 pandemic which has caused more than 900,000 deaths and huge economic and social disruption during 2020 are pinning their hopes on a vaccine.
However British drugmaker AstraZeneca suspended late-stage trials on its potential vaccine this week after an illness in a participant in Britain who was reported to be suffering from symptoms associated with transverse myelitis, a rare spinal inflammatory disorder.The World Health Organization (WHO) has flagged the AstraZeneca vaccine, which is being developed with the University of Oxford, as the most promising for coronavirus.CEO Pascal Soriot said during an online event on Thursday that AstraZeneca did not yet know the diagnosis of the participant who was ill, adding that it was not clear if the volunteer had transverse myelitis and more tests were needed.
Pfizer, BioNTech Report ‘Strong’ Immune Response in Animals to COVID-19 mRNA Vaccine Candidate
Pfizer and its partner BioNTech have five potential COVID-19 vaccines in clinical trials, each of which is based on a different mRNA format. Now the companies are reporting that the most advanced candidate, BNT162b2, performed well in trials in which mice and macaques were infected with the coronavirus after inoculation.The companies announced Wednesday that the vaccine candidate produced neutralizing antibodies against SARS-CoV-2, the virus that causes COVID-19, in macaques, as well as antigen-specific CD4+ and CD8+ T cells in both the nonhuman primates and mice. Those T cell responses indicate a “strong” anti-viral immune attack, the companies said. The results were published on the journal preprint site BioRxiv.
Pfizer and BioNTech reported that after one shot and a booster shot, the macaques that had been challenged with the COVID-19 virus had no viral RNA in their lower respiratory tracts, as compared to non-immunized animals, most of which did show evidence of the viral RNA.According to the study, two shots of BNT162b2 given to the macaques induced COVID-19 neutralizing antibodies at levels that were 10.2 to 18 times higher than those found in convalescent plasma from human patients.