NIAID Launches Trial to Assess Post-Vax COVID Transmission Risk

 Thousands of college students participating in a new trial called PreventCOVIDU will help determine how well COVID-19 vaccines diminish risk of transmitting the infection, officials said Friday.

That the vaccines are highly effective at preventing symptomatic illness is well established.

"But the prevailing question is, when these people get infected, how often is that, if they're asymptomatic, how much virus do they have in their nose?" said Anthony Fauci, MD, President Biden's chief medical advisor and director of the National Institute of Allergy and Infectious Diseases, during a White House briefing. "And do they transmit it to people who are their close contacts?"

The open-label randomized trial, which began on Thursday, will test whether vaccine prevents both infection and transmission of SARS-CoV-2 among college students, and will "help inform science-based decisions about mask use and about social distancing post-vaccination," Fauci added.

The NIH-funded study will include 12,000 college students ages 18 to 26 from more than 20 universities, and is expected to last 5 months, Fauci said. One group of 6,000 students will receive their first dose of the Moderna vaccine immediately. The others will serve as controls and will receive their vaccine 4 months later.

All participants will ultimately receive the usual two doses.

Participants will swab their noses daily for SARS-CoV-2 infection, provide blood samples periodically, and complete surveys through an electronic diary app. They will also be asked to follow their university's SARS-CoV-2 protocols and get tested twice each week, according to the study's website.

Anyone who tests positive will be asked to follow additional protocols.

Another 25,000 individuals whom participants name as "close contacts" -- for example, roommates or co-workers -- will also provide blood samples to the researchers, take daily nose swabs for 2 weeks, and answer weekly questionnaires (if they agree to participate, of course).

"The degree of transmission from vaccinated individuals will be determined by the infection rate in the close contacts," Fauci explained.

The study website indicates that participants will be paid for the daily swab collection, with the precise amount varying among locations and other factors. These details will be reviewed during the informed consent process.

Exclusion criteria for the trial include:

• Self-reported known history of SARS-CoV-2 infection
• Blood products, systemic immunoglobulins, or monoclonal antibodies (including against SARS-CoV-2) received within 90 days before first vaccination
• Investigational research agents received within 30 days before first vaccination

Students who've already received a COVID vaccine dose, have taken an immunosuppressive medication within 168 days, or have "clinically significant medical conditions" are ineligible.

The study was designed and will be overseen by researchers at the COVID-19 Prevention Network (CoVPN), whose headquarters are located at the "Fred Hutch" cancer center in Seattle.

An article about the study posted on the Fred Hutch website says that, while the study will use the Moderna vaccine, results should apply as well to the similar mRNA product developed by Pfizer and BioNTech.

Generalizability to other vaccines, such as the adenovirus-based products from AstraZeneca and Johnson & Johnson, or those in development using synthetic protein antigens, is more speculative. However, most people in the U.S. are receiving the mRNA vaccines.

https://www.medpagetoday.com/infectiousdisease/covid19vaccine/91832