J&J says COVID booster shot significantly increases protection; single-shot durability at least 8 months

Johnson & Johnson released a report Wednesday saying that a COVID-19 booster shot can increase antibodies nine-fold compared to 28 days after a single, first dose.

The news comes on the heels of Johnson & Johnson publishing interim Phase 1/2a data in the New England Journal of Medicine in July that showed people to still have a strong antibody response eight months after a single vaccine dose of Johnson & Johnson.

According to the release, the company conducted a second Phase 1/2a study to test the need for possible vaccine boosters. They say the interim data shows that people who received a second dose showed a fast and robust increase in spike-binding antibodies that were nine-fold higher than a month after the initial shot.

"We look forward to discussing with public health officials a potential strategy for our Johnson & Johnson COVID-19 vaccine, boosting eight months or longer after the primary single-dose vaccination, " said Mathai Mammen, M.D., Ph.D., global head, Janssen Research & Development, Johnson & Johnson.

The booster trial summaries have not yet been published in a medical journal but are being submitted to MedRxiv.

The CDC recently authorized booster shots for people who were immunized with Pfizer or Moderna. People are told to get a booster eight months after their second shot. Until now, no data about possible Johnson & Johnson booster shot studies had been released. The Johnson & Johnson COVID-19 vaccine is authorized by the FDA under the Emergency Use Authorization.