Influenza vaccine trials need participants at Stanford

Cornelia Dekker

The Stanford University School of Medicine is recruiting participants for a set of closely related clinical trials to identify age-related and genetic factors that may explain differences in people’s immune responsiveness to seasonal influenza vaccines.

The studies are recruiting identical twin pairs who are ages 8-30, or 70-100; fraternal twin pairs in the 18-30 or 40-59 age groups; and non-twins ages 70-100. An additional group will consist of non-twins ages 18-30 who did not get the H1N1 influenza vaccination last year. To be useful as “twins,” both members of twin pairs must sign on as study volunteers.

Designed to test various aspects of immune response, the trials are in their second year. More than 200 participants are being sought this season, with identical twins at a particular premium.

“Because these trials have a goal of recruiting new participants each year, there are fewer local volunteers available for this season’s studies,” said Cornelia Dekker, MD, professor of pediatric infectious diseases and medical director of the Stanford-Lucile Packard Children’s Hospital Vaccine Program. “We are making this call for participants now because there is much more flu vaccine available this year, and we are trying to identify participants before they get their flu shot elsewhere.”

The Stanford trials will also compare immune responses to different versions of vaccines, said Dekker, who is responsible for initiating and carrying out clinical trials of vaccines at Stanford.

Older people often have a weaker response to influenza vaccine than younger people do, resulting in a reduced ability of the standard seasonal vaccine to ward off the flu. The trials will compare responses of older people getting the standard influenza vaccine, licensed for this season by the U.S. Food and Drug Administration, with those of people receiving a newly licensed, high-dose vaccine that contains four times as much antigen to boost the immune system as that contained in the standard shot.

In a further comparison, the standard, shot-in-the-arm vaccination will be pitted against vaccination via nasal spray (also approved by the FDA).

The trials are taking place under the aegis of a large National Institutes of Health grant awarded to the medical school. Overseeing the numerous projects entailed in the grant is Mark Davis, PhD, professor of microbiology and immunology, and director of the Stanford Institute for Immunity, Transplantation and Infection.

Blood samples from patients in the influenza vaccine trials will be transferred to numerous researchers, who will analyze hundreds of different substances and cell types from these samples in a coordinated effort to find factors that can help predict a given person’s immune profile and immune response to influenza vaccination.

“Results from these studies may help us develop more effective influenza vaccines, better tests to diagnose influenza and perhaps a simple test that might predict a person’s response to the flu shot ahead of time so we can anticipate who might need extra protection against influenza infection,” Dekker said.

Prospective participants are encouraged to visit a dedicated Web site, http://vaccines.stanford.edu/clinical_trials.html, to review study information and join the volunteer mail list, or call (650) 498-7284 to learn more about their potential eligibility for the trial.

Dekker noted that people considering participation in the trial should be prepared to make three to five separate visits to the Stanford campus within a four- to five-week time period. Those selected to participate will receive a single vaccine dose during one of the visits and undergo blood draws at all of them. While most visits will require a half-hour or less of the participant’s time, the first visit is expected to take between one-and-one-half and two hours because of the informed-consent process and immunization. Enrolled subjects will receive parking vouchers for their visits and compensation for their time ($30 per visit).