JOHANNESBURG – A small South African clinical study has found that AstraZeneca PLC’s Covid-19 vaccine does not appear to protect mild and moderate disease recipients from a new, rapidly spreading strain of virus first detected in the country Sunday.
The study, which enrolled approximately 2,000 volunteers with a median age of 31 years, was too small and its participants were too young to draw broad conclusions about the overall effectiveness of the vaccine in protecting against coronavirus disease, more chosen when it comes to hospitalizations or death. . However, its findings contribute to the concern that a mutant virus makes existing Covid-19 vaccines less effective and that vaccines will need to be updated to protect against new strains of the virus.
Johnson & Johnson and Novavax Inc., whose vaccines have not yet been licensed in any country, also found that their vaccines were less effective in recent human clinical trials in South Africa. But their vaccines have been shown to be still 50% or more effective in preventing mild to moderate cases of Covid-19 and even stronger in protecting beneficiaries from severe disease and hospitalization of the new strain.
Sunday’s press release on the AstraZeneca study in South Africa did not provide a vaccine efficacy rate. The Johnson & Johnson trial in South Africa involved about 6,500 people, while the one in Novavax had 4,400.
The University of Witwatersrand in Johannesburg, which conducted the AstraZeneca study, said it cannot assess whether the vaccine provides protection against more severe cases of Covid-19 because relatively young study participants have a lower risk of developing severe Covid. -19 symptoms.