Respiratory syncytial virus vaccine development
Respiratory syncytial virus (RSV) is a widespread cause of respiratory illness and hospitalizations in infants and children worldwide. Since no vaccine against the virus exists, PATH’s RSV vaccine project is evaluating the feasibility for developing a RSV vaccine that can be delivered using a maternal immunization approach. We are partnering with vaccine developers, universities, government agencies, and other research institutions to speed progress toward such a groundbreaking vaccine, which could help reduce RSV morbidity and mortality as well as the heavy economic burdens associated with caring for the sick.
Advancing an RSV vaccine candidate in the clinic
We are collaborating with vaccine developer Novavax, Inc. of Rockville, Maryland, to advance the development of a RSV fusion (F) protein vaccine candidate, which recently underwent a Phase 2 clinical trial in non-pregnant women of childbearing age in the United States. Results from the study support progression to the next stage of clinical testing. The partners are advancing the vaccine candidate to ultimately be administered to pregnant women so that high levels of maternal RSV antibodies can be transmitted to their newborns before birth, providing protection against infection in the early infancy period when the disease burden is the highest.
Vaccine development portfolio snapshot
Research to support RSV vaccine development efforts
PATH has established several research partnerships to advance the RSV vaccine field and inform on the feasibility of a maternal immunization approach.
Developing tools to test RSV vaccines
Current research suggests that vaccines designed to induce antibodies that neutralize RSV could prevent infection. To improve the accuracy, reproducibility, and efficiency of measuring these essential neutralizing antibody responses, we are collaborating with the US National Institute of Allergy and Infectious Diseases (NIAID) through a team led by Dr. Barney Graham of NIAID’s Vaccine Research Center to optimize a new platform for an RSV neutralization assay (or test). The format will enable scientists to uniformly and objectively assess neutralizing antibody as a measurable sign of protection. It will be an important step toward providing vaccine developers with a means to test and compare RSV vaccines.
We are also collaborating with both Novartis Vaccines and Diagnostics, Inc. and GlaxoSmithKline Vaccines to develop RSV preclinical models for evaluating RSV vaccine candidates for pregnant women. These studies include developing and optimizing in vivo and in vitro models designed to add to the RSV vaccine development toolbox. They will also inform on maternal immunization strategies going forward.
Assessing maternal immunization as an approach to prevent RSV
Other research collaborations are evaluating the feasibility of RSV maternal immunization strategies in the developing world. In healthy populations, transfer of maternal protective antibody to the fetus is very efficient. In populations with chronic infections such as malaria or HIV, antibody transfer may not be as efficient.
We are working with Dr. Ruth Karron at the Bloomberg School of Public Health, Johns Hopkins University; Dr. Christopher King at Case Western Reserve University; and Dr. Willie Pomat and colleagues at the Papua New Guinea Institute of Medical Research to assess how malaria present in the placenta affects the transfer of RSV-specific neutralizing antibody from mothers to infants.
With Dr. Janet Englund of Seattle Children’s Research Institute, we are studying RSV disease burden as well as the transfer and protective effect of maternal-derived RSV antibody in infants in Bangladesh and Nepal.
Under an agreement with the University of Warwick, we are working with Dr. James Nokes through the Kenya Medical Research Institute to evaluate the relationship between maternal RSV-specific antibody and protection in infants. We are also looking at the rate at which antibody protection declines from birth using samples collected from newborns in Kilifi, Kenya.