Johnson & Johnson's COVID-19 vaccine was up to 71 percent effective against hospitalization from infection with the delta variant of the coronavirus in a South African study, The Wall Street Journal reported.
Data released Aug. 6 on a trial of nearly 480,000 healthcare workers in South Africa showed that the vaccine was up to 96 percent effective against death from the delta variant, and 67 percent effective against the beta variant.
The data hasn't been peer reviewed or published in a scientific journal, according to the Journal.
"The vaccine works very well in South Africa and protects against severe disease and death. All the immune responses that we've seen indicate good, immediate and sustained immune response against Delta, and we see surprising durability in immune response of up to eight months," Glenda Gray, one of the study’s lead researchers, told the Journal.
When there were breakthrough cases, Dr. Gray told the Journal that 96 percent of them were mild. Less than 0.05 percent of the cases led to severe disease or death in the trial. There were two rare blood-clotting cases among the workers, but both fully recovered, the Journal reported.
"The data are particularly important because it's a study that was done in the most challenging epidemiologic setting, which is a major surge of the Delta variant in Africa," Dan Barouch, MD, PhD, director of the Center for Virology and Vaccine Research at Beth Israel Deaconess Medical Center in Boston, told the Journal.
Dr. Barouch was involved in the development of the J&J vaccine but not the South African trial.
Johnson & Johnson is also expected to release data on the efficacy of two doses of its vaccine in the coming weeks, the Journal reported.
Read the full article here.