Story at a glance
- Flu vaccine efficacy varies from year to year due to a host of factors.
- In an effort to better protect against influenza, researchers developed a whole-virus vaccine.
- Previous trials showed the vaccine was effective in mice, even against strains not included in its formulation.
A National Institutes of Health (NIH) clinical center in Bethesda, Md., has begun a phase 1 trial of a universal flu vaccine.
Traditional seasonal flu vaccines can reduce the risk of flu illness by 40 to 60 percent each year, according to the Centers for Disease Control and Prevention, while “how well flu vaccines work (or their ability to protect against a certain outcome) can vary from season to season,” the agency states.
Vaccine candidate BPL-1357 was created by researchers at the National Institute of Allergy and Infectious Diseases (NIAID) and will be tested for safety and its ability to prompt immune responses in participants.
Up to 100 healthy volunteers between the ages 18 and 55 can be enrolled in the placebo-controlled, single-site trial. The launch comes after trials conducted in mice and ferrets showed promising responses to the whole-virus vaccine.
BLP-1357 is composed of four strains of non-infectious, chemically inactivated, low-pathogenicity avian flu virus, according to an NIH press release.
“Influenza vaccines that can provide long-lasting protection against a wide range of seasonal influenza viruses as well as those with pandemic potential would be invaluable public health tools,” NIAID director Anthony Fauci said in the release.
“The scientific community is making progress on this pressing global health priority,” he continued, adding the vaccine performed “very well” in pre-clinical studies.
All the mice exposed to two doses of the vaccine survived later exposure to lethal levels of six different flu strains. The vaccine was delivered both intranasally and intramuscularly, and the mice also showed positive reactions to strains not included in BLP-1357.
In the current trial, participants will be randomized to receive two doses of the placebo or two doses of the vaccine, each 28 days apart, with different groups receiving different forms of the inoculation (intramuscular vs intranasal).
Clinicians and participants are both blinded to group assignments and the study is expected to take around seven months to complete, per participant.
“With the BPL-1357 vaccine, especially when given intranasally, we are attempting to induce a comprehensive immune response that closely mimics immunity gained following a natural influenza infection,” said lead investigator Matthew J. Memoli in the release.
“This is very different than nearly all other vaccines for influenza or other respiratory viruses, which focus on inducing immunity to a single viral antigen and often do not induce mucosal immunity.”