By Sola Ogundipe
The AstraZeneca/Oxford vaccine appeared to offer only limited protection against mild disease caused by the South African variant of COVID-19, the results of a new trial have suggested.
Early data from a trial conducted at South Africa’s University of the Witwatersrand and Oxford University showed the two-step vaccine had significantly reduced efficacy against the South African variant, according to a Financial Times report published weekend.
Among coronavirus variants currently most concerning for scientists and public health experts are the UK, South African and Brazilian variants, which appear to spread more swiftly than others.
Although the South African variant hasn’t been officially detected in Nigeria, indications show that it may be already be in circulation in the country.
“In this small phase I/II trial, early data has shown limited efficacy against mild disease primarily due to the B.1.351 South African variant,” an AstraZeneca spokesman said in response to the Financial Times report.
“However, we have not been able to properly ascertain its effect against severe disease and hospitalisation given that subjects were predominantly young healthy adults.”
The company said it believed its vaccine could protect against severe disease, given that the neutralising antibody activity was equivalent to that of other COVID-19 vaccines.
While thousands of individual changes have arisen as the virus mutates into new variants, only a tiny minority are likely to be important or change the virus in an appreciable way, according to the British Medical Journal.
“Oxford University and AstraZeneca have started adapting the vaccine against this variant and will advance rapidly through clinical development so that it is ready for Autumn delivery should it be needed,” the AstraZeneca spokesman said.
The trial involving more than 2,000 people has not been peer-reviewed. The makers had said their vaccine has similar efficacy against the UK coronavirus variant as it does to the previously circulating variants.
Earlier research from the manufacturers – the University of Oxford and biopharmaceutical company AstraZeneca – had showed that a single shot of the vaccine slowed transmission – and that delaying the second dose might be beneficial.
The UK became the first country to approve AstraZeneca’s COVID-19 vaccine for emergency use in December 2020 just weeks after Pfizer’s and Moderna’s respective vaccines received a green light from the Food and Drug Administration in the United States.
Nigeria has been allocated 16 million doses of the vaccine out of the 88 million doses allocated to African countries for the first phase distribution under the COVAX platform tgat is being coordinated by the World Health Organiation.
The Oxford/AstraZeneca vaccine is widely believed to be key to reaching people in rural and underfunded areas because it is cheaper, easier to transport and can be stored at higher temperatures than the Pfizer-BioNTech and Moderna vaccines.