Johnson & Johnson has released data showing that a booster dose to its one-shot coronavirus vaccine provides a strong immune response months after people receive a first dose.

J&J said in statement that it ran two early studies in people previously given its vaccine and found that a second dose produced an increased antibody response in adults from age 18 to 55. The study’s results haven’t yet been peer-reviewed, AP reported.

“A booster dose of the Johnson & Johnson Covid-19 vaccine further increases antibody responses among study participants who had previously received our vaccine,” said Dr Mathai Mammen, global head of research and development at J&J.