A Covid-19 vaccine developed by the University of Oxford and AstraZeneca Plc prevented a majority of people from getting the disease but fell short of the high bar set by Pfizer Inc. and Moderna Inc., according to initial results of a large trial.
Those results look less promising than data from Moderna, which said its shot stopped 94.5% of trial participants from falling ill, according to early data. Pfizer, which is working with German partner BioNTech SE, said its vaccine candidate prevented 95% of symptomatic infections.
Despite the lower efficacy, the British shot has some advantages when it comes to distribution. While the other two have to be stored frozen, the Astra-Oxford jab can be kept at refrigerator temperature, which would make it easier to transport and store globally, particularly in lower and middle-income countries. It also comes at a potentially lower cost.
