Contextualizing the First RSV Vaccine: How Past Failures Informed Current Successes

Yesterday, the US Food and Drug Administration (FDA) approved GSK’s respiratory syncytial (RSV) vaccine, Arexvy (RSVPreF3 +AS01E), to prevent lower respiratory tract disease (LRTD) caused by RSV in adults 60 years and older.

On the heels of the approval of the world’s first RSV vaccine, Contagion interviewed RSV expert Steven Varga, PhD, to find out why it’s taken so long and how soon we can expect RSV vaccines for other at-risk populations.

“RSV is the leading cause of lower respiratory tract infection in infants and small children worldwide,” said Varga. “It’s also one of the top 2 or 3 causes of lower respiratory tract infection in older adults, which is what this first vaccine is targeting.”

Varga is a member of the St. Jude Children's Research Hospital faculty in the Department of Infectious Diseases. He also Dean of the St. Jude Graduate School of Biomedical Sciences. As a professor of microbiology, immunology, and pathology, Varga has studied RSV for over 2 decades.

Varga anticipates we will see more RSV vaccines approved in the next 6 months to a year, most notably a potential maternal vaccination intended to protect infants against RSV before they are born.

RSV was first identified in the 1950s, and Varga explained vaccines have been in development since the 1960s. After an initially promising candidate led to morbidities and mortalities, its development was halted immediately.

“That really impaired our ability to successfully design and develop a vaccine for decades, for fear of recreating that vaccine-enhanced disease that occurred,” Varga said. “I think we know a lot from that failed vaccine trial, it really helped inform how to test vaccines moving forward, and none of the current vaccines have shown any issues with regard to safety concerns.”

This is part 1 of Dr. Varga’s interview. Come back tomorrow for part 2, to hear about the advances and setbacks in treating RSV infection in infants and children.