Johnson & Johnson’s COVID-19 vaccine helps protect against moderate to severe illness, newly published clinical trial results show.
Researchers also found that there was 66 percent efficacy at 28 days post-vaccination and prevention against hospitalization and death across all 44,325 participants.
Variants in the ongoing clinical trial, known as the ENSEMBLE study, included the so-called South African variant and a variant believed to have originated in Brazil.
Efficacy for the vaccine was 64 percent against moderate to severe disease from the South African variant and 68.1 percent against the other.
The data “demonstrate that, with a single shot, our vaccine offers a high level of activity across all variants and regions studied,” said Dr. Mathai Mammen, global head of research and development at Janssen, in a statement. “We believe these data support the important role our COVID-19 vaccine can play in helping to address the global pandemic that continues to threaten people and health care systems around the world.”
Janssen is the pharmaceutical subsidiary of Johnson & Johnson that developed the COVID-19 vaccine, which is also known as Ad26.COV2.S.
The trial “showed the efficacy of a single dose of the Ad26.COV2.S vaccine in preventing COVID-19,” researchers wrote in the journal article.
The randomized, double-blind trial to study the adenovirus vector vaccine is being carried out in multiple countries, including the United States, Brazil, South Africa, and Mexico. The trial is being carried out by Janssen and Operation Warp Speed, a federal government initiative started last year under former President Donald Trump.
Of the trial participants, about half received the jab and about half received a placebo. Of those who got the shot, approximately 10 percent contracted the CCP virus, versus 9.4 percent of those who received the placebo.
The number of moderate to severe COVID-19 cases 14 days after vaccination among the placebo group, 348, was higher than the number in the group that got the shot, 116. Three other people in the former group had symptomatic COVID-19, along with one other person in the latter set.
U.S. officials are probing at least seven cases where patients who got Johnson & Johnson’s shot developed cerebral venous sinus thrombosis, a rare blood clot, in conjunction with low levels of blood platelets. One of the patients died.
“While these events are very rare, we’re recommending a pause in the use of the J&J COVID-19 vaccine in order to prepare the health care system, to recognize and treat patients appropriately, and to report severe events they may be seeing in people who’ve received the J&J vaccine,” Dr. Anne Schuchat, principal deputy director of the Centers for Disease Control and Prevention, told reporters on a call last week.