By Alexander Winning
JOHANNESBURG (Reuters) – Two of the South African government’s top advisers on COVID-19 backed Pfizer’s vaccine on Friday, despite a study showing earlier this week that the dominant local coronavirus variant could reduce the antibodies it causes .
The country is counting on the Pfizer shot, developed with German partner BioNTech, to step up its vaccination program after administering the first dose of Johnson & Johnson on Wednesday.
AstraZeneca vaccinations are suspended after a small local trial found that the shot offers minimal protection against mild to moderate disease against the 501Y.V2 variant that was only identified last year.
The laboratory study published in the New England Journal of Medicine suggested that the 501Y.V2 variant could reduce protective antibodies caused by the Pfizer vaccine by two-thirds.
But scientists quickly warned that it was difficult to judge what it would mean in the real world because the findings of the study came from a laboratory.
Professor Barry Schoub, chair of the Ministerial Advisory Committee on Vaccines, told Reuters that reducing the two-thirds in antibodies mentioned in the study “means there is a significant residue that neutralizes the potential, … we feel Pfizer is still a very good vaccine in our context “.
The advisory committee held its regular weekly meeting on Thursday and discussed the study.
Although it has not been established in a clinical trial that the Pfizer vaccine protects against the more contagious 501Y.V2 variant, “we can have a reasonable extrapolation because it is such a powerful stimulator of the immune system,” Schoub said. said and added that the authorities would do so. closely monitor those receiving the Pfizer vaccine.
Health Minister Zweli Mkhize said on Wednesday that South Africa initially expects 500,000 doses of Pfizer vaccine and by June about 7 million doses.
‘WITHIN PORTABLE LIMITS’
Professor Salim Abdool Karim, another government adviser, said in a separate interview that the reduction in neutralizing activity identified in the study was ‘within the tolerable limits of what we can accept’.
Importantly, he has not yet established that antibodies against the protein that the virus uses to infect human cells are associated with protection.
“This is one of the many hypotheses currently under investigation,” he said, adding: “We do not know what it is in these vaccines that leads to protection.”
Asked if he would tentatively recommend interrupting Pfizer vaccinations, he said: “No, actually the opposite. It is within our acceptable limits of neutralization.”
He said it makes little sense to conduct a clinical study to test the Pfizer vaccine against the local variant, as it has already been adapted with a 501Y.V2 insert. “So if we had to start a clinical study, we would have their new vaccine by the time we get the results,” he continued.
South Africa, with nearly 1.5 million cases and more than 48,000 deaths, recorded almost half of the COVID-19 deaths and more than a third of the confirmed infections in Africa.
This has brought richer countries back with the initiation of its vaccination campaign.
(Reported by Alexander Winning; Edited by John Stonestreet and Nick Macfie)