Moderna vaccine up to 88% effective against COVID in kids 6 to 11 years

Estimated effectiveness of the Moderna COVID-19 vaccine against infection in children 6 to 11 years old was 88% at least 14 days after the first dose amid the Delta variant surge, before the emergence of Omicron, finds an interim analysis from a phase 2/3 clinical trial.

Vanderbilt University investigators led the study, which was conducted at 79 US and 8 Canadian sites and published yesterday in the New England Journal of Medicine (NEJM).

In part 1, the team randomly assigned 751 children aged 6 to 11 to receive 50- or 100-microgram (μg) doses of the vaccine from March to August 2021. After evaluation of safety and immunogenicity, the 50-μg dose was chosen for part 2 of the trial.

In part 2, 4,016 children were randomly assigned in a 3:1 ratio to receive either two 50-μg vaccine doses or a placebo 28 days apart. Follow-up was a median of 82 days.

The vaccine was tied to primarily low-grade, limited adverse events such as injection-site pain, headache, and fatigue. No serious adverse events, multisystem inflammatory syndrome in children, myocarditis, or pericarditis were reported.

One month after dose two, concentrations of SARS-CoV-2 neutralizing antibodies in children given a 50-μg dose were more than twice as high as those in adults 18 to 25 years given a 100-μg dose in a related phase 3 trial. Over 99.0% of the participants in both age-groups had good immune responses.

Estimated vaccine effectiveness in the children was 88.0% (95% confidence interval [CI], 70.0% to 95.8%) against infection at least 14 days after the first dose.

"These results…provide support for the use of this vaccine to prevent Covid-19 in children," the authors wrote.

On Oct 29, 2021, the US Food and Drug Administration expanded the emergency use authorization for the Pfizer/BioNTech COVID-19 vaccine to include 5- to 11-year-olds. Moderna has asked the FDA to authorize its vaccine for kids aged 6 to 11 years and 6 months to 5 years.
May 11 NEJM study

COVID-related inflammation tied to increased death within 1 year

The stronger the inflammation during the initial COVID-19 hospitalization, the greater the probability that the patient will die within a year of hospital discharge, but prescription steroids after discharge appear to lower the risk, according to a study today in Frontiers in Medicine.

University of Florida researchers analyzed data on 1,207 adults hospitalized in 2020 or 2021 for COVID-19 within the university's health system and tracked them for at least 1 year after discharge. To assess the severity of inflammation, they observed concentration in blood of C-reactive protein (CRP) secreted by the liver.

As expected, CRP concentration during hospitalization was strongly correlated with COVID-19 severity. The average was 59.4 milligrams per liter (mg/L) for hospitalized patients who didn't require supplemental oxygen, but it was 126.9 mg/L for those who needed oxygen through noninvasive means and 201.2 mg/L for patients who required mechanical ventilation or extracorporeal membrane oxygenation.

After accounting for other risk factors, the team also found that COVID-19 patients with the highest CRP concentration during their hospital stay had a 61% greater risk of dying of any cause within a year of discharge from the hospital than patients with the lowest CRP concentration.

They also found that the risk of death from any cause associated with severe inflammation was lowered by 51% if patients were prescribed anti-inflammatory steroids after their hospitalization.

First author Arch G. Mainous III, PhD, said in a Frontiers news release, "Many infectious diseases are accompanied by an increase in inflammation. Most times the inflammation is focused or specific to where the infection is.

"Covid-19 is different, because it creates inflammation in many places besides the airways, for example in the heart, brain, and kidneys. High degrees of inflammation can lead to tissue damage."

Mainous said COVID-19 should be seen as a potentially chronic disease, because, after the acute infection stage, it can cause ongoing problems, similar to heart failure or diabetes.

"We may similarly need to start thinking of Covid-19 as having ongoing effects in many parts of the body after patients have recovered from the initial episode," he said.
May 12 Front Med study
May 12 Frontiers news release