Dr. Scott Gottlieb told CNBC on Wednesday it is still possible the Food and Drug Administration will approve Pfizer and BioNTech‘s Covid-19 vaccine for young kids by Halloween.

“I wouldn’t foreclose the possibility that this could be out in October,” said Gottlieb, who sits on Pfizer’s board and served as FDA commissioner for two years under the Trump administration.

Pfizer submitted initial Covid vaccine trial data for kids ages 5 to 11 to the FDA on Tuesday, and the company should file a formal application needed for emergency use approval “shortly,” Gottlieb said in an interview on “Squawk Box” on Wednesday.

The Food and Drug Administration has a lot of experience with the Pfizer vaccine, Gottlieb noted, adding the Covid shot for young kids is the same two-dose regimen as adults but is administered in smaller doses. They have cleared shots for Americans 12 and over.

He stated that the agency has seen many clinical data. It is possible that October will be a reality, although it has been a long-held belief. The possibility of it falling to the middle of November is possible if that happens.

Gottlieb’s remarks come one day after Wall Street Journal reports that the regulatory approval of Pfizer’s vaccine for children aged 5-11 years may be delayed until November.

Last week, Pfizer released new data that showed a two-dose regimen of 10 micrograms — a third the dosage used for teens and adults – is safe and generates a “robust” immune response in a clinical trial of kids ages 5 to 11.

Pfizer had expected to file an emergency use authorization application for vaccine use in children under 5 years old by now, but the company has said that they will not do so until the next few weeks.

The FDA may delay the availability of the vaccines until November, if it spends the same amount time looking at the data as for the 12- and 15-year olds. Pfizer requested that the FDA authorize expanded use of the vaccine in teens on April 9. The FDA granted this authorization on May 10.

Pfizer spokeswoman Jerica Pitts declined to discuss a timeframe for approval. She said that the FDA cannot predict when the FDA will approve the use of the vaccine.

Jerica Pits, spokesperson at Pfizer said that they are on track to submit a formal EUA request very soon.

As children start school, the strain is expected to be approved soon. Many parents want their young children vaccinated. The strain has led to a surge in U.S. hospitalizations, including among young kids who are currently ineligible to get vaccinated.