UI Health Care joins COVID-19 booster shot clinical trial

IOWA CITY — The University of Iowa Health Care has joined a clinical trial to study new regimens of COVID-19 booster shots.

The Iowa City-based health care system is participating in a new Phase 2 clinical trial that will test booster vaccines in various combinations to determine which provide the best immune response against existing and emerging COVID-19 variants.

The trial will study six combinations of new and existing booster shots developed by Moderna.

As more variants emerge, the study aims to prepare for future virus variants that can evade protection from current COVID-19 vaccines, said Dr. Pat Winokur, executive dean of the UI Carver College of Medicine and Vaccine Treatment and Evaluation unit director.

Researchers aim to dive deeper into the science of the immune response to these vaccines, Winokur told reporters Thursday. By doing so, vaccines developers will be able to go back and tweak the shots to create a better antibody response that can protect recipients from even mild illness.

“We were able to develop vaccines that have protected people from serious disease, but we know now that these are not perfect vaccines,” Winokur said. “ … Now what’s really important is going back and trying to fine-tune our understanding of these vaccines, then we can figure out whether there are better vaccines for the variant viruses that are inevitably developing and circulating over time.”

COVID-19 vaccines have been effective in protecting individuals from severe illness, but protection from the shots and from previous infection wanes over time. As a result, experts have seen fully vaccinated individuals experiencing mild illness during the latest surge caused by the omicron variant of the coronavirus.

The trial

UI has received funding for the study — called the COVID-19 Variant Immunologic Landscape (COVAIL) trial — from the National Institute of Allergy and Infectious Diseases, part of the U.S. National Institutes of Health.

The clinical trial is being conducted at 24 sites, including the University of Iowa.

Officials hope to recruit 600 participants aged 18 and older who have already received the primary coronavirus vaccination series and a booster shot at least 16 weeks before enrolling in the study.

They are not yet recruiting volunteers.

Each participant will be randomly assigned one of the six booster regiments that is being studied, which include “investigational” vaccines that have not received formal approval from the U.S. Food and Drug Administration.

Those regimens include:

Participants also will be monitored for symptoms and adverse events following the vaccination, but Winokur said researchers don’t expect those reactions to be any different from those seen in the initial vaccine series and booster shots.

Study participants will return to the clinic over the next 12-14 months to provide blood samples for laboratory analysis of their immune response against coronavirus strains, UI officials said.

Researchers hope to have initial findings by August.

Tweaking the blueprint

Winokur said the process of studying various vaccine regimens is a strategy employed by scientists for many vaccines.

The booster shots to be studied will be the same messenger RNA used in the initial vaccines series, but now scientists are working to “tweak the blueprint,” Winokur said.

“We are not really changing the platform, and we’re not changing how the body reacts to these vaccines,” Winokur said. “We’re just trying to see if exposure to the variants — especially combinations of different variants within the same vaccine — broadens the immune response to protect people better.”

The U.S. Centers for Disease Control and Prevention currently recommends one booster shot of either Pfizer-BioNTech or Moderna COVID-19 vaccine for those aged 12 and older. A booster shot should be given at least five months after the final dose of the initial primary vaccine series, or three months for those who are immunocompromised.

Comments: (319) 398-8469; michaela.ramm@thegazette.com