Pfizer has kicked off an early stage trial of an experimental vaccine against respiratory syncytial virus (RSV) in healthy adult volunteers.

The company is looking to develop the vaccine for populations at highest risk of the respiratory infection - infants through maternal immunisation and older adults through direct vaccination.

The Phase I/II, randomised, placebo-controlled, observer-blind, dose-ranging study will include two age groups - males and females aged 18-49 years and 50-85 years - enrolled in parallel to support both the maternal and older adult indications.

The study’s primary endpoints are safety and tolerability, and its secondary endpoint is immunogenicity.

“RSV is the most frequent cause of serious respiratory tract infection in infants and young children, and also significantly impacts older adults and those with a compromised immune system,” said Edward Walsh, principal investigator, professor of medicine at the University of Rochester, and head of Infectious Diseases at the Rochester General Hospital in New York.

“There is an urgent global need to develop a safe and effective vaccine as a preventative option to reduce the incidence and severity of this infection in these populations.”

“A successful RSV vaccine has been an elusive goal for the global health community for decades, but recent scientific achievements have prepared the field to potentially tackle this important pathogen,” added Kathrin Jansen, senior vice president and head of Vaccine Research and Development at Pfizer.

“By pursuing a vaccine candidate to help protect both infants and older adults, we hope to make an impact for those most at risk for RSV disease.”