Johnson & Johnson said on Friday, 29 January that its single-dose vaccine was 66% effective in preventing COVID-19.
The vaccine was proven to be 72% effective against moderate and severe disease in the United States, the company said. The vaccine, however, was found to be 85% effective in preventing severe disease across all regions studied, 28 days after vaccination in all adults.
The study showed the level of protection against COVID-19 varied from 72% in the United States, to 66% in Latin America. The concerning issue is that the efficacy has been proven to be only 57% in South Africa.
Johnson & Johnson plans to seek emergency use authorisation from the US Food and Drug Administration and already has plans to deliver one billion doses of the vaccine.
Johnson & Johnson’s vaccine uses a common cold virus to introduce corona virus proteins into cells and trigger an immune response, whereas the Pfizer/BioNTech and Moderna vaccines use a technology called messenger RNA, reported Reuters.
The vaccine was found to be 85% effective in preventing severe disease across all regions studied, 28 days after vaccination in all adults. Efficacy against severe disease increased over time with no cases was reported among vaccinated participants after day 49.
The COVID-19 vaccine candidate demonstrated complete protection against COVID-related hospitalization and death, 28 days post-vaccination. There was a clear effect of the vaccine on COVID-19 cases requiring medical intervention (hospitalization, ICU, admission, mechanical ventilation, extracorporeal membrane oxygenation) with no reported cases among participants who had received the Janssen COVID-19 vaccine, 28 days post-vaccination, a statement on their website read.
Vaccines from Pfizer/BioNTech and Moderna showed around 95% efficacy in the trials, against J&J’s trial data that shows 57% in South Africa, reported Reuters.
In the J&J trial that was conducted in eight countries, 44% of participants were from the United States, 41% from Central and South America, and 15% from South Africa.
The number made the J&J shares go down by 4% at $162.7 at 1700 GMT, while Moderna’s stock gained 8% to $172.80.
Several recent studies have shown that a South African variant of COVID-19 has mutated in a few areas which is one of the reasons for the reduced efficacy of the vaccine.
Dr. Paul Offit, a vaccine expert at the University of Pennsylvania and a member of the FDA’s Vaccines and Related Biological Products Advisory Committee, told CNN that under normal circumstances, there might not be much of a market for a vaccine that is significantly less effective than two others already on the market.
But considering the extent of the pandemic and shortage of vaccine, he along with several health workers opined that a vaccine that is inexpensive, a single dose, and has no cold chain requirements, will be received well in the market.