If everything goes as planned,
According to, Pfizer has fully enrolled adolescent trials and Moderna is currently enrolling 3,000 adolescents in a safety and reactogenicity trial known as , in which participants will receive an intramuscular injection of 100 mcg mRNA-1273 on day 1 and on day 29. Meanwhile, Johnson & Johnson and AstraZeneca will be starting to enroll older children and adolescents into studies within the next several weeks.
The companies are also planning to enroll younger children, Dr. Maldonado, the Taube professor of global health and infectious diseases at Stanford (Calif.) University, said during thepre-AAD meeting. “At least two of the vaccine companies have indicated that they would like to start enrolling children as young as 2-5 years of age and eventually getting down to infants and toddlers if the vaccines prove to be safe and effective in the older children. Eventually, we hope to get to the level where we can have several vaccine candidates for all children 6 months of age and older.”
In the future, she said, infectious disease experts hope to see antiviral, immunomodulatory, anti-inflammatory, and monoclonal therapies for all populations including children, although trials in this population have not begun. “Clinical trials must be flexible and adaptive to deal with children and adolescents,” added Dr. Maldonado, who is also senior associate dean for faculty development and diversity at Stanford.
“We would ideally like to have new correlates of protection, as well as biomarkers to follow for evidence of effectiveness. We also would love to see vaccines in the pediatric population as soon as possible, because herd immunity is the ultimate goal for protection against this disease and prevention of additional transmission over time.” However, she said, the degree and durability of immunity has yet to be determined, and vaccine-associated immune effects are unknown. In the meantime, infectious disease researchers expect nonpharmacologic interventions, such as wearing face masks and social distancing to continue for an undefined period.
(Less than 2 weeks after Dr. Maldonado spoke at the SPD meeting, Pfizer announced in a press release that, in phase 3 clinical trials, the company’s coronavirus vaccine was 100% effective in protecting children aged 12-15 years from infection, with a “robust” antibody responses and side effects similar to those experienced by those aged 16-25 years. The company also announced that it plans to seek Food and Drug Administration EUA for this age group. Asked to comment on this update, Dr. Maldonado said the results released by Pfizer “suggest that their COVID-19 vaccine is very safe and highly effective in preventing COVID-19 among children 12-15 years of age.” She added that additional data from the Pfizer trials as well as from Moderna and Johnson & Johnson vaccine trials “will hopefully lead to FDA EUA review in the coming weeks,” and that COVID-19 vaccinations for children “may be possible by this summer.”)