On Wednesday, the staff at Food and Drug Administration struck a positive tone. Johnson & JohnsonCovid-19 booster shot, which may have some benefit following the second dose.

However, staff admitted that data on boosters is limited. The agency still hasn’t validated all information.

“Although not independently confirmed by FDA from datasets, summaries of the data suggest there may be a benefit in a second dose administered approximately 2 months after the primary dose, when compared to the efficacy seen in the pivotal study COV3001,” they wrote in a 54-page document made public Wednesday.

They also said one J&J dose was consistently less effective than the mRNA vaccines made by Pfizer and Moderna in clinical trials and in real-world studies.

According to them, “The Janssen COVID-19 Vaccine has consistently shown lower effectiveness than other mRNA COVID-19 vaccines in clinical trials.”

Overall, data shows the single-shot J&J vaccine “still affords protection against severe COVID-19 disease and death in the United States.”

The report by FDA scientists is meant to brief the agency’s Vaccines and Related Biological Products Advisory Committee, which meets Friday to discuss data on the safety and effectiveness of a second J&J shot in adults. The agency offers a glimpse into its view of additional shots in the documents that were published.

Unlike Pfizer and Moderna’s two-shot mRNA vaccines, J&J hoped to offer a one-shot solution that would protect the public enough to help bring an end to the pandemic. However, its 72% protection in the U.S. was seen as less than Moderna’s and Pfizers’ vaccines which boasted efficacy rates higher than 90%.

A second dose of J&J’s shot boasts similar performance to the mRNA vaccines, boosting protection from symptomatic infection to 94% when administered two months after the first dose in the United States, according to company data released Sept. 21. J&J, which uses a modified adenovirusIn order to induce an immune response, requested the agency to approve a booster dose of its single-dose vaccine for adults 18 and older.

The FDA advisory group is scheduled to discuss data on the safety and effectiveness of Moderna’s booster shot in adults on Thursday and J&J’s on Friday. It is possible that the agency will make its final decision in the days following the meeting. Then, it could hand the information to the Centers for Disease Control and Prevention and the vaccine advisory committee for their decision next week.

FDA scientists declined to take a stanceIn an unusual decision Tuesday, Moderna made a controversial move to support booster shots for Moderna’s Covid vaccine. The data showed that vaccines currently approved in the U.S. still provide protection against serious disease.

U.S. regulators were last month authorized Covid booster shots of Pfizer and BioNTech’s vaccine to a wide array of Americans, including the elderly, adults with underlying medical conditions, those who work or live in high-risk settings like health and grocery workers.

Norman Baylor, the FDA’s former vaccines director, stated last week that he wouldn’t recommend Moderna’s vaccination to any advisory committee, as it shares a platform with Pfizer’s shot. This vaccine has been approved for boosters. However, J&J is different.

It “gets a little bit more tricky” because a second dose of J&J’s vaccine appears to boost “extremely well,” Baylor said. It might have needed to be a double-dose. [vaccine]At the beginning

This story is still in development. Keep checking back for more updates.