New Brunswick, New Jersey – On Wednesday, Johnson & Johnson announced that a second dose of its one-shot Covid-19 vaccine significantly increased antibody levels to fight the virus.

Studies by Johnson & Johnson have shown that a second-dose of its one-shot vaccine provided a "rapid and robust increase in spike-binding antibodies," according to the company's website.

Antibodies are the immune system's frontline defense against infections, such as Covid-19.

The company conducted two studies looking at the safety and side effects of a second shot for those who had already received the Johnson & Johnson vaccine, both the US and Europe.

Results showed that a booster dose generated a significant increase in antibodies, nine times higher than are present 28 days after the initial dose. These responses were observed in those between the ages of 18 and 55, and those 65 and older who received a lower dose of the vaccine.

"We have established that a single shot of our Covid-19 vaccine generates strong and robust immune responses that are durable and persistent through eight months," Mathai Mammen, the global head at Janssen Research & Development, said in a statement on the company's website.

Johnson & Johnson is currently in talks with the US Food and Drug Administration (FDA) regarding the need to offer a booster dose.

"With these new data, we also see that a booster dose of the Johnson & Johnson COVID-19 vaccine further increases antibody responses among study participants who had previously received our vaccine," Mammen said.

The booster shot would likely be a second dose of the same Johnson & Johnson vaccine that was initially administered.

These findings were shared just two days after the FDA announced its full approval of the Pfizer vaccine.