KEY POINTS
  • J&J scientists randomly assigned healthy adults between the ages of 18 and 55 and those 65 and older to receive a high or low dose of its vaccine — called Ad26.COV2.S — or a placebo.
  • Most of the volunteers produced detectable neutralizing antibodies, which researchers believe play an important role in defending cells against the virus, after 28 days, according to the trial data.
  • By day 57, all volunteers had detectable antibodies, regardless of vaccine dose or age group, and remained stable for at least 71 days in the 18-to-55 age group.

Johnson & Johnson's one-dose coronavirus vaccine is safe and appears to generate a promising immune response in both young and elderly volunteers, according to trial data published Wednesday in the New England Journal of Medicine.

J&J scientists randomly assigned healthy adults between the ages of 18 and 55 and those 65 and older to receive a high or low dose of its vaccine — called Ad26.COV2.S — or a placebo. Some participants in the 18-to-55 age group were also selected to receive a second dose of the vaccine.