The CEO of Moderna says he expects his company’s vaccine to be available for kids as young as 5 to receive it this fall. Moderna is currently testing the vaccine on children as young as six months, but says more testing must be done before it can be considered for use.

““I think it’s going to be early fall, just because we have to go down in age very slowly and carefully,” said CEO Stephane Bancel during an online event Monday.

The Moderna news comes as Pfizer reveals it’s also testing its vaccine on children between the ages of 5 and 11 years of age. The pharmaceutical company will also begin testing the vaccine in infants as young as six months in the next few weeks. The Pfizer clinical trial will involve up to 4,500 patients at clinics in the United States, Spain, Finland and Poland. The company hopes to apply to the FDA in September for emergency authorization of the vaccine for children in the 5-11 age bracket. Results for children between 2 and 5 could be available soon after that, according to a Pfizer spokesperson.

The Pfizer-BioNTech coronavirus vaccine was approved last month to be used for children ages 12-15.

Word that vaccines for young children could come in the next few months is encouraging for continuing to contain and prevent the COVID-19 virus from spreading. With roughly half of U.S. adults fully vaccinated, getting the vaccine in children’s arms would appear to be the clearest path to halting the spread, say health officials.