March 16 (UPI) -- A federal agency is recruiting volunteers for two Phase 2 clinical trials for a vaccine against H7N9, a strain of avian influenza that has not reached humans in the United States.
The National Institute of Allergy and Infectious Diseases, which is part of the National Institutes of Health, wants an effective vaccine ready for any H7N9 pandemics.
The trials, which will last 16 months, will test the effectiveness of different dosages of the inactivated influenza vaccine candidate, called 2017 H7N9 IIV, in conjunction with other vaccines.
The virus strain was first reported in humans in 2013 in China. Subsequently, six waves of H7N9 infection have occurred there, resulting in 1,565 human infections and 613 deaths, according to the World Health Organization in January.
Right now, people typically become infected through direct exposure to infected poultry or contaminated environments, and not from person to person. But if the virus mutates and becomes easily transmissible between humans, it could result in a pandemic, the NIH warns.
Because most people have little to no immunity to it, 39 percent of those who becme infected would die, the NIH predicts.
"As we experience one of the worst seasonal influenza epidemics in recent years here in the United States, we also must maintain a scientific focus on novel influenza viruses, such as H7N9, that have the potential to cause a pandemic," Dr. Anthony S. Fauci, director of the National Institute of Allergy and Infectious Diseases, said in a press release. "These new clinical trials will build upon initial studies of earlier versions of an H7N9 vaccine candidate to provide a more detailed picture of its safety and ability to generate a protective immune response to current H7N9 strains."
The vaccine has been developed by Sanofi Pasteur with support from the Biomedical Advanced Research and Development Authority, a component of the U.S. Department of Health and Human Services.
During the clinical trials, some participants will receive an adjuvant, called AS03, along with the test vaccine. The adjuvant is used to enhance the body's immune response to an antigen.
In all groups, participants will receive one dose at the first visit and another 21 days later.
One study will enroll as many as 420 male and non-pregnant female volunteers ages 19 to 64 years and up to 300 volunteers older than 65 in Decatur, Ga., Iowa City, Iowa, Baltimore, Durham, N.C., and Seattle.
The second study will test the H7N9 vaccine candidate with AS03 adjuvant in conjunction and a quadrivalent seasonal influenza vaccine. They plan to enroll 150 healthy volunteers ages 19 to 64 total in Birmingham, Ala., Baltimore, Cincinnati and Nashville.
Enrollment has already started at the University of Alabama at Birmingham School of Medicine's Alabama Vaccine Research Clinic.
"We are excited for the opportunity to have UAB play a part in testing the H7N9 vaccine candidate, as its effectiveness could shape the way that this strain of avian influenza is treated across the world," Dr. Paul Goepfert, director of the Alabama Vaccine Research Clinic, said in a press release. "We know that new flu viruses will continue to present themselves, and we need to be prepared to protect humans against those potential strains as they become a threat."