Photographer: Gen Shkullaku / AFP / Getty Images
Photographer: Gen Shkullaku / AFP / Getty Images
AstraZeneca Plc’s coronavirus vaccine did not offer much protection against mild diseases caused by the variant that emerged in South Africa in a study prompted the country to look for other vaccines last month.
The vaccine had an efficacy of only 10% against the variant variety, according to the study published Tuesday in New England Journal of Medicine. There were no cases of serious illness either in the group that received two injections of the vaccine or in the one that received false shots.
The study did not answer the biggest question facing the vaccine: whether it would protect patients from serious illness and hospitalization, in part because the participants in the trial were young. The only serious side effect pointed out – another key indicator as European countries investigate reports of blood clots – was a high fever after the first dose.
The Astra vaccine is backed by the regulator as safety review increases
South Africa paused at the vaccine launch after publishing some preliminary data from the study last month. The data published on Tuesday was more detailed and its publication in a medical journal indicates that it was peer-reviewed.
The study included about 2,000 participants who had a mean age of 30 years. Older people are usually more affected by the infection.
The vaccine prevented about 22% of all cases of mild to moderate Covid. About 93% of the trial cases were caused by the South African variant. Determining the level of efficacy against the strain was a secondary objective of the study.