Vaccine Study To Help Prevent Most Common Viral Causes Of Childhood Respiratory Illness

Armen Hareyan's picture

Childhood Respiratory Illness

MedImmune is dosing at-risk children six months to 24 months of age in a Phase 1 trial of a vaccine designed to help prevent respiratory syncytial virus (RSV) and parainfluenza virus type 3 (PIV-3) infections.

These are two of the most important causes of lower respiratory tract illness and hospitalization in infants and young children. A previously completed study in healthy adults and non-susceptible older children demonstrated that this RSV/PIV-3 vaccine candidate had an acceptable safety profile and was well tolerated.


"As a leader in pediatric medicine, MedImmune is dedicated to developing additional therapies that can help protect infants and young children against potentially serious, even fatal, respiratory illnesses," said Genevieve Losonsky, M.D., vice president, clinical development, infectious disease. "Advancing this vaccine candidate targeting two very prevalent childhood respiratory infections underscores our continued commitment to scientific innovation and may potentially address a significant unmet medical need."

Designed to evaluate safety, tolerability, immunogenicity, and vaccine shedding in the nose, MedImmune's Phase 1 dose-escalation trial is a multi-center Northern Hemisphere study to be initiated when RSV is not widely circulating in the community. In the study, more than 140 study participants will be followed through the end of the subsequent RSV season or for 180 days after the final dose, whichever occurs later.

In addition to the RSV/PIV-3 vaccine candidate to be used in this study, MedImmune researchers are working through a Cooperative Research and Development Agreement (CRADA) with the National Institute of Allergy and Infectious Diseases (NIAID), part of the National Institutes of Health (NIH), to develop live, attenuated intranasal vaccines designed to reduce the consequences of disease caused by RSV; PIV types 1, 2 and 3; and human metapneumovirus (hMPV). These viruses are responsible for more than half of all hospitalizations for pediatric respiratory tract disease and are important causes of bronchiolitis, pneumonia and/or croup.

Each year, an estimated 125,000 infants in the U.S. are hospitalized with severe RSV infections. RSV is the most common respiratory infection in infancy or childhood that circulates in the Northern Hemisphere predominately in the winter months. Approximately one-half of all infants are infected with RSV during the first year of life, and nearly all children have been infected at least once by the time they reach their second birthday. Children born prematurely as well as those with CLD or congenital heart disease (CHD) are at high risk for severe disease and hospitalization due to RSV. The virus may also cause severe illness in other high-risk groups such as the elderly, those with underlying respiratory or cardiac disease, and those with compromised immune systems (e.g., bone marrow transplant patients).

PIV-3 is second only to RSV as the cause of viral pneumonia and bronchiolitis in young children and infants. PIV-3 is responsible for more than three million physician visits and more than 30,000 hospitalizations each year in the United Sates alone. As with RSV, PIV-3 infects the majority of infants in the first two years of life.