UW Studying Potential COVID-19 Vaccine Booster

SEATTLE — A UW Medicine trial could help us learn more about COVID-19 vaccines, and may be the key to developing booster shots to prolong immunity.

In the rush to end the pandemic, national health experts decided there was no time for prolonged study of the Moderna, Pfizer and Johnson & Johnson vaccines. As a result, though the vaccines have been widely distributed, patients have been left with a few questions about those vaccines — one of the biggest being the question of how long the vaccines are effective, and how we might be able to extend the immunity they bestow.

In an effort to answer that question, UW Medicine, along with 11 other sites across the country, have begun a booster trial to see if administering another round of vaccines will help ward off disease.

Their trial is particularly novel because it is what UW calls a "mix 'n match" trial, administering a dose of the Johnson & Johnson vaccine to all patients: including those who have previously taken the Moderna or Pfizer vaccines, or those who have had not previously been vaccinated at all.

“We just want to be ready for whatever this virus throws at us,” said UW Medicine's Dr. Christine Johnson, principal investigator and an associate professor of medicine. "So right now, we're trying to understand whether giving a booster shot with what currently available vaccines, EUA-approved vaccines, will improve the immune response.”

Pfizer has also been in talks with top U.S. health officials about potentially using a third dose of its vaccine as a booster shot. The company claims a third shot of its vaccine can cause antibody levels to jump five-to-tenfold, the Associated Press reported.

But as Johnson explains, this study is necessary to answer many lingering questions about how vaccine boosters may work.

"We want to have the evidence about whether boosters are effective or not," Johnson said. "And right now, I think we still need a lot more data to understand when to get boosters, how to get them, and how to phase them, the timing – and so that is exactly what this trial is trying to address.”

For its trial, UW Medicine is seeking volunteers 18 years and older who have either:

• Received their final dose of an EUA vaccine at least 12 weeks ago.
• Have yet to be vaccinated, but are willing to take an EUA vaccine as well as a booster. Those patients who have yet to be vaccinated will be given the 2-dose Moderna vaccine, followed by the J&J booster at a later date.

Trial organizers say they expect to monitor volunteers for about a year, including physical exams and blood draws following their injections.

“Right now, we're just trying to gather that evidence base so that we are prepared for the fall or whatever comes next with this virus,” Johnson said.

Volunteers interested in joining the study can learn more by calling UW Medicine at (206) 520-4366 or by emailing joinuwcovid19vax@uw.edu.