It is extraordinarily rare for young children to become seriously ill with covid-19, but they do become infected and can spread the virus to others. So if we want to interrupt transmission and achieve herd immunity, they have to enter the vaccination campaign equation. Preliminary results from the trials that Pfizer and Moderna Pharmaceuticals, whose COVID-19 vaccines are based on messenger RNA, are conducting in the pediatric population could be available before the summer.
The four vaccines approved so far by the European Medicines Agency (EMA) – Pfizer/BioNTech, Moderna, AstraZeneca and Janssen – are testing their respective formulations in children.
On the one hand, Pfizer, whose vaccine has been used since the age of 16 in the US, has already applied for emergency authorization from the US regulator (FDA) for use in children between 12 and 15 years of age and has recruited 4,600 children between six months and 11 years of age to carry out phases 1, 2 and 3 of its trials with children in the US and Europe. “Children younger than 6 months of age can be evaluated at a later date, once an acceptable safety profile has been established,” explains the company, which expects to have preliminary results in the second half of this year 2021 and regulatory clearance “in early 2022.”
Moderna is testing its vaccine in 3,000 children aged 12 to 17 years and has announced a next phase of its ‘KidCOVE’ study with a sample of 6,750 children that it will divide into two groups: from six months to the second year of life, and from two to 11 years. The trials are being carried out in the USA and Canada.
AstraZeneca, for its part, is in the middle of Phase 2 trials of its vaccine, based on chimpanzee adenovirus, in 300 children aged between six and 17 years (150 between six and 11 years and 150 between 12 and 17 years).
Janssen, the other EU-approved vaccine also based on adenoviruses – both backed by the EMA following their “possible link” to the “very rare” cases of thrombosis combined with thrombocytopenia – is testing its efficacy and safety in a sample of 660 adolescents aged 12 to 17 years.