J&J vaccine effective against Delta in South Africa’s Sisonke trial

Doses of the Johnson & Johnson Janssen Covid-19 vaccine are seen at a vaccination clinic during an Atlanta Braves baseball game at Truist Park in Atlanta, Georgia, U.S., on Friday, May 7, 2021. The Atlanta Braves will be providing free COVID-19 vaccinations for fans during their games Friday and Saturday against the Philadelphia Phillies. Each person who gets vaccinated is eligible to receive two free tickets to a future Braves game. Photographer: Elijah Nouvelage/Bloomberg

The single-dose J&J shot was 71% effective against hospitalization and as much as 96% effective against death.

See also this report from the presentation on Friday: Oxford/AstraZeneca to make a comeback and provide boost to national drive

Johnson & Johnson’s Covid-19 vaccine helps prevent severe disease among those infected with the delta variant, according to a trial involving almost 480,000 health workers in South Africa.

The study, known as Sisonke, provides the first large-scale evidence that the J&J vaccine works against this dominant variant, according to trial co-lead Glenda Gray. It’s probably more protective against delta than it was with the earlier beta strain, she said in a presentation Friday.

The single-dose shot was 71% effective against hospitalization and as much as 96% effective against death, she said. It also demonstrated durability of eight months.

“These results show there is no need for a booster yet,” said Gray, who is president of the South African Medical Research Council.

While the J&J vaccine is a key element to South Africa’s vaccination plan, the country temporarily paused its use in April after the U.S. decided to suspend the shot because of its link to rare blood clots. Other data have raised questions about how well the shot holds up against the highly contagious strain that has driven renewed outbreaks in countries including the U.S. and China.

What Bloomberg Intelligence says:

“Being a single-shot vaccine, we worry that there could be a faster and deeper drop off in risk reduction against hospitalization at the later points of six or eight months for J&J, even though there’s a comment that protection lasts up to eight months.”

— Sam Fazeli, BI senior pharmaceutical analyst

One U.S. study released last month showed the J&J shot produced relatively low levels of antibodies against delta. J&J said that analysis, which hasn’t been published in a peer-reviewed journal, had examined only one aspect of protection and didn’t consider long-lasting responses among immune cells stimulated by the vaccine. The drugmaker’s researchers have said their own data indicated that the vaccine neutralizes the variant and that additional doses weren’t needed.

Africa’s Rollout

Earlier this year J&J agreed to supply as many as 400 million vaccines to the African Union through the end of 2022, delivering a boost to a continent trailing most of the world in the race to inoculate. The dose’s requirement for just a single shot is seen as beneficial for Africa, where vaccine distribution to more than 1 billion widely dispersed people is likely to present a challenge.

Read more: A Covid Booster for Everyone?

In the study, the vaccine was administered to the health workers at 120 sites in both urban and rural areas from Feb. 17 to May 17. Analysis of a third data set is expected in coming days.

There were two cases of the rare clotting disorder thrombocytopenia thrombosis syndrome among participants, with both making a complete recovery, Gray said. DM –  By Janice Kew and Antony Sguazzin for Bloomberg. 


"Information pertaining to Covid-19, vaccines, how to control the spread of the virus and potential treatments is ever-changing. Under the South African Disaster Management Act Regulation 11(5)(c) it is prohibited to publish information through any medium with the intention to deceive people on government measures to address COVID-19. We are therefore disabling the comment section on this article in order to protect both the commenting member and ourselves from potential liability. Should you have additional information that you think we should know, please email [email protected]"

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