Children’s vaccines on the verge of approval: What do we know about them?

Last Friday (22.10.21) published The Food and Drug Administration of the United States (FDA) presented the data submitted by Pfizer ahead of the convening of the Advisory Committee this coming Tuesday, as part of its transparency policy. In the clinical trial of the corona vaccine in children aged 11-5, 4,640 children participated: 3,109 received the vaccine and 1,531 received a placebo vaccine as a control. The trial was conducted in three stages as usual, with the first stage examining the safety of the vaccine and the second and third stages, conducted in parallel, examining the efficacy, rarer side effects and the effectiveness of the vaccine in preventing symptomatic disease. The vaccine given to children was three times lower than the adult vaccine (10 micrograms instead of 30 per dose), and as in the other age groups, they received two doses of vaccine, three weeks apart.

In the experiment, the researchers looked for side effects in close proximity to the vaccine, measured the level of antibodies in their blood and their ability to neutralize corona viruses under laboratory conditions, and of course examined how many participants were exposed to corona in the experimental and control groups. It is important to emphasize that like other clinical trials here too the trial was conducted under double blindness, i.e. both the person who gave the vaccine and the person who received it did not know if they received the real vaccine or were in the control group. The data were revealed only after enough children had been infected in Corona. This is the currently accepted clinical protocol, designed to prevent biases and interventions on the part of the pharmaceutical company.

The trial results were very similar to trials in adults and adolescents, showing that the vaccine was about 91 percent effective in preventing symptomatic disease with mild and transient side effects, similar to results in the other age groups of adolescents and adolescents. The results reveal two important data: one, in no group (trial or control) was severe morbidity recorded in corona, which is rare in children. Because the vaccine is very effective in preventing serious illness in adults, and due to the great similarity in the other indices, it can be estimated that the vaccine also protects children from serious illness. The second important statistic is that no case of myocarditis, a rare side effect associated with the vaccine, has been identified. This is probably due to the size of the sample, which is not sufficient to detect such a rare side effect, which is estimated to The most severe Stands at about 1: 6,000 in young boys (ages 30-16). The advisory committee will likely instruct health authorities to pay attention to this side effect, especially in the coming months.

Pfizer corona vaccines | Photo: Reuters

Benefit vs. risk

One of the dilemmas that the FDA committee will face is considering the benefit of the vaccine, as opposed to possible harms from rare side effects. In the weekend Published by the FDA His scientists’ first reference to the results of the experiment. Their report included risk assessments for children from vaccine side effects versus risk from the disease in six scenarios based on data from different morbidity periods, while assessing side effects according to side effects aged 17-12. The only case where there was no significant benefit to the vaccine (whites only) was in a scenario where morbidity was very low (similar to last June in the US) and vaccine efficacy is only 70 percent. This is a very unlikely scenario at the moment, especially when the morbidity in the US On the rise And already higher. However, the researchers noted that the risk assessment is based on data for older age groups and three times the dose of the vaccine. Their conclusion was that even in the age group 5-11, the benefits of the vaccine significantly outweigh the potential risks. It is important to remember that in children, although the complications of the disease are relatively rare, they still exist in considerable frequency (for example, a 1: 3,000 risk of life-threatening multisystem inflammation) that is manifested when the morbidity is very high, as happened in Israel last summer.

It is estimated that the committee will give the vaccine an emergency permit, similar to the permits it has given so far for the youth vaccine And for the adult vaccine And the US administration already Began to prepare For an extensive vaccination campaign that will begin immediately after approval. In the country they will probably make a decision At a later stage, but with the aim of reaching a situation where the majority of the Israeli population is vaccinated against Corona, in order to prevent a significant fifth wave.

By Editor

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