COVID

January 6, 2022

Grant boosts vaccine effectiveness research

by Nancy Humphrey

Investigators at Vanderbilt University Medical Center have received a $10.7 million research award from the Centers for Disease Control and Prevention (CDC) to continue the IVY Research Network, originally created in 2019 to look at how well flu vaccines work at preventing severe flu illness, and expanded in 2021 to enroll patients hospitalized with COVID-19.

It’s the third renewal for the collaborative IVY (The Influenza and Other Viruses in the Acutely Ill) Network, consisting of 21 large adult hospitals in 21 U.S. cities, funded by the CDC and led by VUMC.

Their work includes one of the first descriptions of Long COVID syndrome, data demonstrating different effectiveness among COVID vaccines being used in the U.S. and the effectiveness of COVID-19 mRNA vaccines for lessening illness severity among adults who develop COVID, despite vaccination.

Wesley Self, MD, associate professor of Emergency Medicine and Vice President for Clinical Research Networks and Strategy at VUMC, is principal investigator for the IVY Network.

Wesley Self, MD, MPH

“We are greatly honored to have this opportunity to continue to work with the CDC and fantastic collaborators across the country on understanding severe COVID-19 and how to optimize vaccination in the U.S.,” Self said. “We still have a lot to learn about how to prevent and successfully treat COVID. We are very happy that the IVY Network has been able to contribute knowledge about COVID over the past three years, and we are excited to expand on this work.”

Beginning in December 2020, when COVID vaccines became available, the IVY Network started enrolling as many people as possible who were hospitalized for COVID at 21 hospitals across the country, Self said, adding that hospitalized patients without COVID were also enrolled as a control sample.

The IVY Network has published dozens of original research manuscripts about research findings, including in the Journal of the American Medical Association, Morbidity and Mortality Weekly Report, and Clinical Infectious Diseases.

In May 2021, the IVY Network showed that MRNA vaccines (from Pfizer and Moderna) are 87% effective in preventing hospitalizations with COVID. “It was a remarkable number. It was stunning to see how effective they are,” Self said.

Then in August 2021, the IVY researchers were also the first to show that the Pfizer vaccine, although very effective in preventing COVID (88%), is not quite as effective as the Moderna vaccine (93%).

Also in August, as there were more breakthrough cases, the group dove into looking at whether the mRNA vaccines prevented critical illness in those who were hospitalized with COVID.

“The answer was a resounding yes,” Self said. “People who get COVID after being vaccinated are far less severely ill than those who are infected and haven’t been vaccinated,” he said. “That was pretty exciting. We’ve been trying to show that for years in influenza, but have never been able to clearly show it is true. It’s clearly true in COVID.”

The network also looked at how long protection lasts.

“In July we saw that things were starting to wane. Protection was still good, but clearly your risk for COVID goes up three to four months after vaccination,” Self said. “Clinical trials only measured protection for a few months, but we want people to be protected for the rest of their lives,” he said.

Going forward, the IVY Network will help answer two questions: whether current vaccines provide adequate protection against new variants, or if new vaccine formulations are needed; and when is the best timing for booster vaccinations?

The network also plans to continue studying influenza and to study respiratory syncytial virus (RSV), “an underappreciated cause of severe illness in adults, especially older adults,” Self said.

“Vaccines against RSV are currently in development, and we want to understand as much as we can about influenza and RSV, and from that information will study how vaccines are working to prevent severe illness. It’s a great opportunity to expand beyond COVID and into two of the other major causes of illness in this country.”

Others integral to the IVY network at VUMC include Natasha Halasa, MD, MPH, and James Chappell, MD, PhD, who run the IVY Network viral laboratory, as well as Christopher Lindsell, PhD, H. Keipp Talbot, MD, Carlos Grijalva, MD, Todd Rice, MD, Jonathan Casey, MD, Ian Jones, MD, Bo Stubblefield, MD, Adrienne Baughman, Kim Hart, Christina Kampe, Kelsey Womack, PhD, and Jillian Rhodes, PhD.