Moderna's coronavirus vaccine for children under the age of five is safe and effective, according to FDA reviewers in a briefing document released late Friday ahead of a meeting about granting an emergency use authorization.

Moderna filed an emergency use permission request with the FDA in April for the vaccination of children aged 6 months to under 6 years.

The Biden government declared this week that it has made 10 million COVID-19 vaccine doses ready for young children and newborns in anticipation of the authorization being approved. The first doses should be available by June 21.

Pfizer and BioNTech have also asked for emergency use of their coronavirus vaccine for children. The FDA's outside experts will review Pfizer and BioNTech's vaccine on Monday. The CDC's advisory committee will meet on June 17 and 18 to approve the vaccinations developed by the firms.

The FDA warned that the vaccine's effectiveness estimates were based on only a few cases of COVID-19. The agency also stated that children, like adults, would most likely require a booster shot.

According to the Times, FDA reviewers concluded that the Moderna vaccine for children did not cause cases of inflammation of the heart muscle and surrounding tissue, known as myocarditis or pericarditis, a rare side effect that is a risk for young men who receive the Moderna or Pfizer shots.

The Food and Drug Administration (FDA), which independently reviewed data from Moderna's clinical studies, discovered that vaccine efficacy versus symptomatic Covid-19 cases was 51% in babies aged six months to less than two years old and 37% in children aged two to five years.

"Although the VE (vaccine efficacy) ... in children six months to five years is lower than that observed in the pivotal adult or older pediatric studies, it is highly consistent with real-world vaccine effectiveness observed against Omicron in adults," the FDA said.

Since the trials for very young children were done during a wave linked to the Omicron variant, the figures are lower than those observed in adult clinical trials, according to the FDA.

Even though Moderna's vaccine is less effective against the Omicron strain of the disease, the FDA highlighted that it is still effective against severe instances.

As a result, the FDA concluded that the Moderna data "supports the administration" of the vaccine in two doses of 100 micrograms per teenager aged 12 to 17, 50 micrograms in children aged 6 to 11, and 25 micrograms in toddlers aged 6 months to 5 years.