While four coronavirus vaccine candidates have now entered into late-stage clinical trials among adults, some may wonder when children will be enrolled.

Pharmaceutical giant Johnson & Johnson, for example, announced Wednesday it is moving ahead with a Phase 3 trial of a single-shot dose to treat the virus that causes COVID-19, enrolling 60,000 adults from diverse backgrounds, including significant representation from those that are over 60 years old, to test for efficacy.

Meanwhile, other companies on the coronavirus vaccine front, like Moderna and Astra Zeneca (though the latter is on pause in the U.S. for a safety matter) enrolled people aged 18 and older, while a recent proposed trial expansion by Pfizer and BioNTech looks to include those as young as 16.

A recent article published in Oxford Academic by lead author Dr. Evan Anderson, associate professor at Emory University School of Medicine, urged Phase 2 clinical trials for pediatric COVID-19 vaccination "should begin now" and be conducted "in parallel" with Phase 3 clinical trials for adults.

While four coronavirus vaccine candidates have now entered into late-stage clinical trials in adults, some question when children will be tested. (iStock)

While four coronavirus vaccine candidates have now entered into late-stage clinical trials in adults, some question when children will be tested. (iStock)

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Anderson said delaying clinical trials among children will "delay our recovery from COVID-19 and unnecessarily prolong its impact upon children’s education, health and emotional well-being," adding that "data support the initiation of careful pediatric Phase 2 clinical trials to evaluate safety and immunogenicity of advanced COVID-19 vaccine candidates."

Dr. Melissa Stockwell, chief of child and adolescent health in the department of pediatrics at Columbia University Vagelos College of Physicians and Surgeons, shared similar sentiments.

“Any pandemic vaccination strategy needs to include children if we want to make a real impact in ending the pandemic and in re-establishing important normal routines for children, including returning to school in-person,” Stockwell wrote to Fox News. “The first step, which should begin now, is to conduct careful Phase 2 pediatric trials to evaluate safety in children for vaccines that have shown safety in adults.”

Jeff Richardson, speaking on behalf of Inovio Pharmaceuticals, told Fox News that “in general, industry practice is to begin clinical trials for most infections/diseases with adults and enroll younger subjects in later trials."

Dr.  Anna P. Durbin, professor of international health in the Johns Hopkins Bloomberg School of Public Health with a joint appointment in the School of Medicine, said “the safety and efficacy of the vaccine needs to be determined in those at highest risk of COVID-19 disease first because they will be receiving the vaccine first. Children will not likely be included in the first, highest priority of vaccine recipients.”

Meanwhile, a Moderna spokesperson told Fox News of plans to initiate pediatric vaccination trials for COVID-19 by the end of the year.

“Moderna shares the urgency associated with assessing COVID-19 vaccine candidates in children,” the spokesperson wrote in an emailed statement to Fox News. “Now that Moderna has sufficient safety data in adults, we intend to start pediatric trials by the end of this year, subject to regulatory approval.”

Due to regulatory discussions underway at Moderna, no further details were disclosed about timing, protocols or funding.

Several spokespeople for a number of companies leading coronavirus vaccine trials told Fox News that plans with pediatric vaccination trials will advance after safety and efficacy data is confirmed among adults (iStock).

Several spokespeople for a number of companies leading coronavirus vaccine trials told Fox News that plans with pediatric vaccination trials will advance after safety and efficacy data is confirmed among adults (iStock).

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At the same time, Jake Sargent, a spokesperson with Johnson & Johnson, echoed similar plans.

“We can confirm that our compound development plan will also include studies evaluating the global population (children, pregnant women, individuals at high risk of severe respiratory disease),” Sargent wrote in an emailed statement to Fox News. “We will only move forward with that after data from adults is analyzed.”

Serious outcomes from COVID-19 are rare among children, though complications do happen. A spokesperson for Astra Zeneca told Fox News the company intends to test more vulnerable populations before enrolling kids into clinical trials.

“The current priority is to gather evidence on the potential of the vaccine to protect populations that are more vulnerable to severe outcomes,” Brendan McEvoy, spokesperson for Astra Zeneca, wrote to Fox News in an emailed statement. “Enrolment [sic] of children will start once sufficient data are gathered in adults, indicating that AZD1222 has the potential to be safe and protective in children.”

“Further knowledge of the epidemiology of COVID-19 in children will contribute to inform vaccine development strategies in children,” McEvoy added.

Fox Business’ Daniella Genovese contributed to this article.

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