Johnson & Johnson (JNJ) announced Tuesday that its booster shot provides even greater protection against COVID-19 when administered in a second dose.

The drugmaker said that the shot has a 94% effectiveness against COVID-19 when administered two months after the first dose and increases antibody levels by as much as four to six times compared with a single dose of the vaccine.

J&J said the vaccine’s safety “remained consistent and was well-tolerated” as a booster shot. Side effects were also consistent with those seen with the single-dose COVID vaccine, the company said.

Six months after the first shot, the booster dose also appeared to offer more protection against the virus with antibodies produced twelvefold higher four weeks after the second shot, regardless of the age of the recipient, the company said.

“Our large real-world evidence and Phase 3 studies confirm that the single-shot Johnson & Johnson vaccine provides strong and long-lasting protection against COVID-19-related hospitalizations,” Mathai Mammen, global head at Janssen Research & Development at Johnson & Johnson, said in a statement.

“Additionally, our Phase 3 trial data further confirm protection against COVID-19-related death. Our single-shot vaccine generates strong immune responses and long-lasting immune memory. And, when a booster of the Johnson & Johnson COVID-19 vaccine is given, the strength of protection against COVID-19 further increases.”

Johnson & Johnson said it has provided the data on its booster shot to the Food and Drug Administration and also plans to submit it to the World Health Organization as well as National Immunization Technical Advisory Groups worldwide as needed.

“We now have generated evidence that a booster shot further increases protection against COVID-19 and is expected to extend the duration of protection significantly,” said Paul Stoffels, vice chairman of the executive committee and chief scientific officer at Johnson & Johnson.

According to the Centers for Disease Control and Prevention, over 14.8 million Americans have received the Johnson & Johnson COVID vaccine.

The news of Johnson & Johnson’s booster shot effectiveness comes a few days after Pfizer received authorization of its booster shot for people 65 and older on Friday. Moderna and Pfizer booster doses are authorized for individuals who are immunocompromised.

As of Tuesday premarket hours, shares of Johnson & Johnson were trading at $164.91, up $1.10, or 0.67%.

US experts say the Johnson & Johnson Covid vaccine should be administered US experts say the Johnson & Johnson Covid vaccine should be administered Photo: AFP / Joseph Prezioso