Booster doses of Johnson & Johnson's one-shot coronavirus vaccine generated a big spike in antibodies, the frontline immune system defenses against infection, the company reported Wednesday.

NEW BRUNSWICK, N.J. - Johnson & Johnson said Tuesday it has asked the U.S. Food and Drug Administration to authorize a booster shot for its single-dose COVID-19 vaccine as the government looks to ...

Do I need a booster if I got the Johnson & Johnson vaccine ... in the U.S. as early as the fall for those who got the two-shot Pfizer and Moderna vaccines, recipients of the single-dose J&J ...