Parents hoping to get their youngest children vaccinated against COVID-19 got some encouraging news Monday.

Pfizer said three small doses of its vaccine offer strong protection to youngsters under 5, according to preliminary data. That news comes a month after Moderna said it would ask regulators to OK its two doses for the youngest kids.

But a few steps remain before the shots are available. Health officials and their expert panels must first decide they are safe enough and provide enough protection to authorize them.

FDA REVIEW

U.S. Food and Drug Administration vaccine chief Dr. Peter Marks has pledged the agency will “move quickly without sacrificing our standards” in evaluating tot-sized doses from both Pfizer and Moderna.

The FDA has tentatively set a June 15 date for its scientific advisers to publicly review the two companies’ vaccines. After the advisers weigh-in, the FDA determines whether to authorize the shot.

Moderna is seeking clearance for two low-dose shots for children under age 6 while Pfizer hopes to offer three extra-low doses to kids under age 5 — differences due to how each company studied its vaccine. Currently, the U.S. recommends vaccinations for everyone age 5 and older, and Pfizer is the only option for those children. Moderna for now is used only in adults in the U.S.

CDC REVIEW

If either vaccine is cleared for the littlest kids, the Centers for Disease Control and Prevention would have to recommend whether all babies, toddlers, and preschoolers should receive them or only those at high risk of a serious illness.

The CDC would convene its own panel of advisers to debate the recommendation before issuing its official guidance.

ROLLOUT

The Biden administration has said the shots will roll out rapidly, and most tots are expected to be vaccinated in pediatricians’ offices or health clinics. It’s not clear how much demand there will be to vaccinate the youngest kids, however. Pfizer shots for 5- to 11-year-olds opened in November, but only about 30% of that age group have gotten the recommended initial two doses.