South African scientists to discuss Pfizer vaccine study 

 South African scientists will hold discussions on Thursday on a laboratory study that suggests the dominant local variant of the coronavirus may reduce antibody protection from Pfizer’s Covid-19 vaccine by two-thirds. 

The government is counting on the Pfizer shot, developed with German partner BioNTech, to ramp up its Covid-19 vaccination programme in the coming months after administering the first Johnson & Johnson doses on Wednesday. 

The study, published in the New England Journal of Medicine, comes less than two weeks after interim data on AstraZeneca’s Covid-19 shot also raised concern about its efficacy against the more infectious South African variant, prompting the government to put the roll out of the AstraZeneca vaccine on hold. 

The detailed laboratory study took into account all the key mutations of the 501Y.V2 variant, whereas a paper published in late January only assessed the impact of three key mutations of the variant on the Pfizer vaccine. 

While its findings are concerning, scientists said that because they come from a laboratory study, it was not easy to extrapolate what they might mean for the shot’s efficacy in real-world scenarios where the variant is prevalent. 

However, real-world but preliminary data from trials of Covid-19 vaccines from AstraZeneca and Novavax have already shown their efficacy is significantly reduced against the variant first identified by South African genomics experts late last year. 

“I do know that our scientists will be meeting to discuss it (the Pfizer study) and they will advise the minister,” health ministry spokesman Popo Maja said. “We are not going to be releasing a statement until advised by our scientists.” 

Barry Schoub, a professor and chair of the Ministerial Advisory Committee on vaccines, said scientists would be holding their regular weekly meeting later in the day and would discuss the study alongside information on other Covid-19 vaccines. 

Asked to comment on the findings, he told Reuters: “The Pfizer vaccine is enormously effective at 95%, so even if there is quite a significant reduction there still will be quite a bit of remnant efficacy left.” 

“It is very likely that it will protect to a reasonable extent, certainly against severe illness and mild to moderate to some extent. That’s the expectation.” 

Monitoring Recommended 

Linda-Gail Bekker, a professor and co-lead investigator in the local arm of Johnson & Johnson’s global phase III trial, said she would recommend that the country do the same kind of monitoring of the Pfizer vaccine it will do for J&J’s shot, which is being rolled out in a so-called “implementation study” to further evaluate it in the field. 

“We should make sure we do see the effectiveness we (are) hoping for,” she told Reuters. 

Health Minister Zweli Mkhize said on Wednesday the country was expecting 500,000 doses of the Pfizer vaccine initially and about 7 million doses by June. 

A spokesman for regulator SAHPRA said Pfizer’s registration application was currently under review and declined further comment. 

South Africa, with nearly 1.5 million cases and about 48,500 deaths, has recorded almost half the Covid-19 fatalities and over a third of confirmed infections in all of Africa. It has lagged wealthier Western nations in launching its immunisation campaign. 

The government plans to vaccinate 40 million people, or two-thirds of the population.