Pfizer Inc and BioNTech SE said on Monday their Covid-19 vaccine induced a robust immune response in five to 11-year-olds, and they plan to ask for authorisation to use the vaccine in children in that age range in the United States, Europe and elsewhere as soon as possible.

The companies said the vaccine generated an immune response in the five to 11-year-olds in their Phase II/III clinical trial that matched what they had previously observed in 16 to 25-year-olds. The safety profile was also generally comparable to the older age group, they said.

"Since July, pediatric cases of Covid-19 have risen by about...