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Covid vaccine ‘100% effective’ in 12-15-year-olds, says Pfizer


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The Pfizer Covid vaccine is estimated to be 100% effective in adolescents aged 12-15, the manufacturer has announced.

And the first healthy children were given doses last week as part of Pfizer’s concurrent phase 1/2/3 study of its vaccine in those aged six months to 11 years, it said in a press statement released today.

It comes amid reports that children could be vaccinated against Covid-19 as soon as August.

Early results from a phase three trial of 2,260 adolescents aged 12-15 in the US demonstrated a vaccine efficacy of 100%, with 18 Covid cases in the placebo group of 1,129 compared with none in the vaccinated group of 1,131, Pfizer said.

The vaccine, given to those with both with and without evidence of prior Covid infection, caused ‘robust antibody responses’ one month after the second dose that exceeded those reported in an earlier trial of 16-25 year-olds, it said.

And it was ‘well tolerated’, with side effects ‘generally consistent with those observed in participants 16 to 25 years of age’, it added.

All trial participants will be monitored for ‘long-term protection and safety’ for two years after their second dose, Pfizer said.

The data is not yet submitted for scientific peer-review but the manufacturer said it plans to do so for ‘potential publication’.

And it plans to submit the data to the FDA and EMA to expand the use of the vaccine into the group ‘as quickly as possible’, it added.

Meanwhile, Pfizer announced that it last week started delivering its vaccine to ‘healthy’ children aged 5-11 as part of its phase 1/2/3 study in children aged six months to 11 years.

The global trial is evaluating the ‘safety, tolerability, and immunogenicity’ of the vaccine on a two-dose schedule approximately 21 days apart across three age groups – children aged five to 11 years, two to five years and six months to two years, it said.

Rollout to the 2-5 year-old cohort is expected to start next week, it added.

Pfizer chairman and CEO Albert Bourla said: ‘We share the urgency to expand the authorisation of our vaccine to use in younger populations and are encouraged by the clinical trial data from adolescents between the ages of 12 and 15.

‘We plan to submit these data to FDA as a proposed amendment to our Emergency Use Authorisation in the coming weeks and to other regulators around the world, with the hope of starting to vaccinate this age group before the start of the next school year.’

CEO and co-founder of BioNTech Ugur Sahin added: ‘The initial results we have seen in the adolescent studies suggest that children are particularly well protected by vaccination, which is very encouraging given the trends we have seen in recent weeks regarding the spread of the B.1.1.7 UK variant.’

The University of Oxford is currently undertaking a study to assess the safety and strength of immune response to the Oxford/AstraZeneca vaccine in children.

A Government scientific adviser previously said that the Covid vaccine will ‘almost certainly’ be rolled out to children later in the year.

Currently, the Oxford vaccine is only authorised for use in the over 18s, while the Pfizer vaccine is being used as a ‘suitable alternative for those 16-17 years of age’ who are eligible for vaccination as part of phase one.