April 14, 2021 by Bethany Rundell
Roundup: Vaccines Highly Effective in ‘Real-World Conditions’; U.S. Trial to Enroll 12,000 College Students; and Adolescents Get 100% Protection, Study Says
CDC: Moderna, Pfizer Vaccines Highly Effective in Preventing Infection in ‘Real-World Conditions’
A new study from the U.S. Centers for Disease Control and Prevention (CDC) finds there is “strong evidence” that the Moderna and Pfizer-BioNTech vaccines are highly effective in preventing COVID-19 infections “in real-world conditions among healthcare personnel, first responders, and other essential workers,” according to a news release by the U.S. agency.
These groups are more likely than the general population to be exposed to the virus because of their occupations.
The study examined the effectiveness of the vaccines in preventing infections among 3,950 study participants in six states over a 13-week period from December 14, 2020 to March 13, 2021. These groups of essential works “are more likely than the general population” to be exposed to the coronavirus because of their frontline occupations, the CDC said.
The results found that after the second dose of either vaccine, risk of infection was reduced by 90 percent two or more weeks after vaccination. Following a single dose of either vaccine, the risk of infection from COVID-19 was reduced by 80 percent two or more weeks after vaccination. Both Moderna and Pfizer-BioNTech vaccines require two doses — four weeks (Moderna) and three weeks (Pfizer-BioNTech) following the initial dose.
It takes about two weeks following each dose of vaccine for the body to produce antibodies that protect against infection. As a result, people are considered “partially vaccinated” two weeks after their first dose of vaccine and “fully vaccinated” two weeks after their second dose.
“This study shows that our national vaccination efforts are working,” said CDC Director Rochelle P. Walensky, MD, MPH. “The authorized mRNA COVID-19 vaccines provided early, substantial real-world protection against infection … These findings should offer hope to the millions of Americans receiving COVID-19 vaccines each day and to those who will have the opportunity to roll up their sleeves and get vaccinated in the weeks ahead. The authorized vaccines are the key tool that will help bring an end to this devastating pandemic.”
The new study’s findings are consistent with those from Phase 3 clinical trials conducted with the vaccines before they received “Emergency Use Authorizations” from the U.S. Food and Drug Administration. Those clinical trials evaluated vaccine efficacy against COVID-19 disease, while this study evaluated vaccine effectiveness against infection, including infections that did not result in symptoms.
Major U.S. Trial to Determine If Those Vaccinated Can Transmit Virus to Close Contacts
A large-scale, U.S. government study involving 12,000 college students at more than 20 universities was launched March 25th with the goal of answering critical questions related to the extent of protection offered by the current COVID-19 vaccines, according to Anthony Fauci, M.D., the chief medical adviser to President Biden and a member of the White House Coronavirus Task Force.
“We hope that within the next five or so months we’ll be able to answer the very important question about whether vaccinated people get infected asymptomatically, and if they do, do they transmit the infection to others,” explained Dr. Fauci at the White House press briefing when he announced the start of the trial.
The study will help determine how often, if at all, do vaccinated people get infected. And if they get infected and are asymptomatic — or presenting no symptoms — “how much virus do they have in their nose and do they transmit it to people who are their close contacts?” said Dr. Fauci, who is also director of the National Institute of Allergy and Infectious Diseases (NIAID), part of the U.S. National Institutes of Health
The “randomized controlled study” will involve college students between 18 and 26 years of age. The students are going to be randomized into two groups: 6,000 will receive the vaccine immediately and another 6,000 will be vaccinated with a delay of four months later. Both of these groups are going to receive the Moderna vaccine regimen of two doses administered 28 days apart.
The participants will complete questionnaires with a digital diary application. They will swab their nose daily to determine if they’ve been infected. And they will provide periodic blood samples.
Additionally, the students will identify a total of about 25,000 individuals as “close contacts.” They will also provide swab and blood samples. The degree of transmission from vaccinated individuals will be determined by the infection rate in the close contacts.
“Again, this will help inform science-based decisions about mask use and about social distancing — post vaccination,” Dr. Fauci said.
Pfizer-BioNTech: COVID-19 Vaccine 100% Effective in Trial With Kids Ages 12-15
Pfizer-BioNTech, the co-makers of one of three U.S.-approved COVID-19 vaccines, says a new clinical trial has found that its vaccine produces “100% efficacy and robust antibody responses” in adolescents from 12 to 15 years old. The trial enlisted 2,260 participants, but the data has yet to be reviewed by the U.S. Food and Drug Administration (FDA).
Pfizer and its vaccine partner BioNTech said they will submit the study’s results “as soon as possible” to the FDA and Europe’s primary drug regulatory agency. The drug company will seek to expand authorizations for the vaccine’s use in young people.
In the placebo-controlled trial, none of the 2,260 participants who received the real vaccine developed COVID-19, Pfizer-BioNTech said. Eighteen adolescents who received doses of the placebo, or fake vaccine, became infected with the virus, the companies said.
“We plan to submit these data to FDA as a proposed amendment to our Emergency Use Authorization 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,” said Albert Bourla, chairman and chief executive officer, Pfizer, in a news release.
At this time, the Pfizer-BioNTech vaccine is authorized for use only in those as young as 16. The two companies are testing the vaccine in children as young as 6 months. In the first part of that study, a group from 5 to 11 years old got their first shots last week. A second group, ages 2 to 5, are scheduled to get their first doses next week.