A Year of RSV Highs and Lows, with Tina Tan, MD

It has been, as much as it can be for a single disease, a banner year for advancing respiratory syncytial virus (RSV) pharmacology in 2023.

First, the US Food and Drug Administration (FDA) approved adjuvant RSV vaccine Arexvy (RSVPreF3 +AS01E) for adults ≥60 years old in May—the first vaccine indicated to prevent the potentially deadly seasonal virus in older adults.¹ Next, the FDA approved a second vaccine—Abrysvo—for the same population 1 month later.²

Another month after that, the FDA approved monoclonal antibody nirsevimab (Beyfortus), for the indicated use of preventing lower respiratory tract disease in newborns and infants at risk of RSV.³

The series of new marketed indication of vaccines and the targeted biologic—specifically for the oldest and youngest populations—speak to the priority of preventing severe RSV disease or even mortality in the most vulnerable age groups every season. They also speak to the growing concern around RSV in an era of fluctuating and increasingly volatile viral waves. For as assured as clinicians may be with the addition of 2 new vaccines and a monoclonal antibody this year, they remain challenged by the unpredictable nature of RSV.

For This Year in Medicine 2023, Contemporary Pediatrics Editor Joshua Fitch spoke with Editor-in-Chief Tina Tan, MD, FAAP, FIDSA, FPIDS, professor of pediatrics, Feinberg School of Medicine, Northwestern University, pediatric infectious diseases attending, Ann & Robert H. Lurie Children's Hospital of Chicago, on the numerous breakthroughs to highlight the evolving fight against RSV in 2023.

Tan discussed the “several surges” of RSV spread that which occurred out of the standard season this year—for reasons that are still not understood by experts.

“But it was the Fall surge which started earlier that really was incredible, because we also were having surges of influenza as well as COVID,” Tan said. “And what that ended up doing was it overwhelmed the pediatric healthcare system so that there really were few to no hospital beds that were available at any given time.”

Tan discussed the introduction of nirsevimab to the market—a celebrated breakthrough that has since been challenged by inventory and significant demand during this particularly difficult past year of cases.

“When nirsevimab was first approved, there were parents that were literally calling and clamoring to try and get the vaccines or the monoclonal antibody for their babies,” she said. “It really has been a challenge for individuals to get an adequate supply of nirsevimab; nobody has an adequate supply.”

Looking ahead to the 2023 - 24 RSV season, Tan did note that certain regions of the US are reporting surges of new cases.

“It still remains to be seen how effective the limited amount of nirsevimab being given and maternal immunization being uptaken will have in terms of impacting the amount of severe RSV disease that we're seeing,” Tan said. “My hope is that there is going to be some impact—it might not have been as great as we would have liked to seen, but I would hope that there would be some impact with the use of the nirsevimab available and the maternal vaccination on the amount of severe RSV disease that may occur.”

References

1. ^{Cosdon N. FDA Approves Arexvy, the First RSV Vaccine for Older Adults. HCPLive. Published May 3, 2023. https://www.hcplive.com/view/fda-approves-arexvy-first-rsv-vaccine-older-adults}
2. ^{Cosdon N. FDA Approves RSV Vaccine for Older Adults. HCPLive. Published June 1, 2023. https://www.hcplive.com/view/fda-approves-rsv-vaccine-older-adults}
3. ^{Parkinson J. FDA Approves Nirsevimab for RSV in Infants. Contagion. Published July 17, 2023. https://www.contagionlive.com/view/fda-approves-nirsevimab-for-rsv-in-infants}