Two additional investigational vaccines appear to generate an immune response against SARS-CoV-2, the New York Times reports.
In one study, appearing today in the Lancet, researchers from Oxford University and AstraZeneca report results from their phase 1/2 single-blind, randomized controlled trial of their vaccine, called ChAdOx1 nCoV-19, which targets the viral spike protein. They report that a single dose of their investigational vaccine yields an increase in spike-specific antibodies by day 28 and neutralizing antibodies after a booster dose.
At the same time, researchers from CanSino Biologics and elsewhere in China report results from their randomized, double-blind, placebo-controlled, phase 2 trial in the Lancet. They found their investigational Ad5-vectored COVID-19 vaccine — which also targets the spike protein — could also generate an immune response to the spike protein after a single dose by day 28.
A commentary in the Lancet from Naor Bar-Zeev and William Moss from Johns Hopkins Bloomberg School of Public Health note that while these results "augur well for phase 3 trials," care should be taken moving forward as the "success of COVID-19 vaccines hinges on community trust in vaccine sciences, which requires comprehensive and transparent evaluation of risk and honest communication of potential harms."
"Seeing these responses means that people should be optimistic that this vaccine will be useful," Oxford's Adrian Hill adds at the Times. "But there is no guarantee until you have shown efficacy in humans because you can't know what you don't know."
A third firm, Moderna, reported last week that its investigational vaccine appears to also generate an immune response.