Booster dose ups antibodies, says J&J

A booster dose of Johnson & Johnson’s vaccine sharply increased levels of antibodies, according to interim data from two early-stage trials, the company said yesterday.

A second dose of the J&J single-dose vaccine resulted in binding antibody levels nine times higher than the levels 28 days after people received their first dose.

Unlike neutralising antibodies, which destroy the virus, binding antibodies attach to the virus but do not destroy it or prevent infection. Instead, these alert the immune system to its presence so white blood cells can be sent to destroy it.

There has previously been no evidence about the effect of a booster of the J&J vaccine. The US CDC advisers, in particular, have been waiting for a word on it.