Johnson & Johnson said on Friday that the single-dose Covid-19 vaccine reduces the rate of moderate to severe illness, but the shot seems less effective in South Africa, where a new coronavirus variant has become commonplace.
Overall, the vaccine was 66% effective in preventing moderate to severe disease 28 days after vaccination. However, the effectiveness varied depending on geography. The shot was 72% effective among volunteers in clinical trials in the US, but 66% among those in Latin America, and only 57% among those in South Africa. Although significantly below the levels seen with the first two authorized Covid-19 vaccines, it is higher than the thresholds originally set by the U.S. Food and Drug Administration to consider a vaccine useful.
The vaccine reduced serious illness by 85% alone, preventing Covid-related hospitalization or death, Johnson and Johnson said.
“In a pandemic, if you can eliminate the serious consequences of death, hospitalization and serious illnesses very quickly with a single dose vaccine, it is important for society,” said Paul Stoffels, head of the company.
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Eric Topol, director and founder of the Scripps Research Translational Institute, calls the results ‘disappointing’, but adds that a vaccine that prevents the most serious consequences, such as hospitalization and death, is still valuable. “It reinforces how lucky we were that the first two were more effective,” he added.
The results started a new phase in the fight against the SARS-CoV-2 virus, which causes Covid-19. Different vaccines against the virus appear to have different levels of efficacy, but also different properties that can make it more or less valuable in some contexts.
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The results of the first two authorized vaccines, one from partners Pfizer and BioNtech and a second from Moderna, were significantly stronger, reducing the symptomatic infection by approximately 95%. But the vaccines require two doses. It also has challenges for distribution because they have to stay at ultra-cold temperatures.
The new variant of the virus first identified in South Africa, B.1.351, throws another monkey key into the equation. Vaccines seem to be less effective. Novavax, another vaccine manufacturer, said on Thursday that the vaccine is 90% effective in the UK, but only 49% in South Africa. The existence of such a variant raises the possibility that vaccine manufacturers will have to develop shots to protect against it. They will even have to do this regularly, as new strains of the coronavirus emerge.
The efficacy of authorized vaccines appears to be somewhat reduced by the B.1.351 strain in test tube experiments, but has not yet been tested in clinical research against it.
“The policy implications of different vaccines with different levels of efficacy are huge,” said Carlos del Rio, a Professor of Infectious Diseases at the Emory University School of Medicine. “To deal with this pandemic and stop the spread, I think you’re using all the tools in the toolbox.”
The J&J results came from an interim analysis of a study of 44,325 volunteers in which 468 symptomatic cases of Covid-19 occurred. They were unveiled Friday morning at a news conference with the National Institutes of Health, which helped conduct the study as part of the U.S. vaccine effort known as Operation Warp Speed. Because the study is still ongoing, the data may still change.
Unlike the Pfizer / BioNTech and Modern vaccines, which are based on a new technology called mRNA, which uses the body’s own cells to produce a vital virus protein, the J&J vaccine uses a type of virus called an adenovirus to produce genes that produce the same virus proteins. A similar technology was used in the vaccine developed by the University of Oxford and AstraZeneca.
J&J said the trial did not result in any significant safety issues over the vaccine. A case of stroke in one volunteer, which led investigators to interrupt this trial, was determined not to be related to the vaccine, Stoffels said. Fever occurred in 9% of those who received the vaccine, and fever of more than 104 degrees occurred in 0.2% of the vaccine recipients. Serious side effects were more common among those receiving placebo than the vaccine.
No matter the age of volunteers in the study, the vaccine appears to have a strong efficacy, Stoffels said. There was concern that its effectiveness would be less strong in older people.
Akiko Iwasaki, a virologist at Yale University, said the results were strong for both the Novavax and J&J vaccines. She noted that it is difficult to compare the J&J results with those of other trials because the previous trials count cases of mild Covid-19, while the J&J study only includes diseases.
Regardless, Iwasaki stressed the importance of vaccinating as many people as possible, given the current lack of immunity in the majority of the population and the large number of cases giving the virus the opportunity to mutate more frequently.
“We need to get the first dose for as many people as possible,” Iwasaki said. ‘These varieties, which are more transmissible and possibly more deadly, are increasing. I think the time is really what we are fighting against. ”
Kert Viele, a statistician from Berry Consultants, made a similar point. The approval of more vaccines and the expansion of the global supply could mean that communities achieve herd immunity, in which enough people are vaccinated against a pathogen to stop transmission chains. “If we can reduce global cases,” Viele said, “we will reduce the rise of all these tribes to the benefit of all, and hence the need for such reformulations in the future.”
One hope is that the effectiveness of the Johnson & Johnson vaccine could increase if given as a two-dose regimen. Johnson & Johnson is conducting another large study enrolling 30,000 patients and testing two doses of the vaccine given 57 days apart. However, substances said and waited so long between doses will delay the results. He expects the results of the two-dose study to be read out in the summer or fall.
The population in the study was “diverse and broad,” J&J said. Patients come from the USA (44%), Central and South America (41%) and South Africa (15%). Women made up 45% of the study and men 55%. Among the participants worldwide, 59% were white, 45% Spanish or Latinx, 13% were black, 6% were Asian and 1% were Indian. Volunteers had health conditions including obesity, type 2 diabetes, high blood pressure and HIV.
The J&J vaccine will be much easier to disperse than the mRNA vaccines made by Moderna and Pfizer / BioNTech. The vaccine will remain stable at -4 degrees Fahrenheit for two years, and will remain stable for up to three months if kept between 36 degrees and 46 degrees Fahrenheit.
Johnson & Johnson is expected to submit to the FDA for an emergency use authorization in early February, and if it is accepted that the vaccine is authorized, some product will be ready to ship immediately after it is approved. The company did not want to give details on how many would be available, other than to say it would enter into all of its offering commitments in 2021.