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Up to 80,000 young kids get hospitalized with RSV each year in the U.S, and it was especially bad this past season. But there's a new drug that could bring those numbers down significantly. Tarryn Mento of member station WAER in Syracuse says it could be available for kids as soon as this year. And a quick note - the American Lung Association, with support from Sanofi, is an NPR sponsor.
TARRYN MENTO, BYLINE: Cheryl Meany was excited to learn she was carrying twins after a tough time getting pregnant. But then doctors had frequent worries throughout her pregnancy about whether the babies would even make it. So she wasn't prepared when her husband suggested, before the twins were even born, that they enrolled them in an experimental study aimed at protecting them from respiratory syncytial virus, also known as RSV.
CHERYL MEANY: It took me aback. Like, what are you even talking about? I don't even know what you're asking me right now.
MENTO: That was in 2014, long before the latest RSV surge. But Cheryl knew about it even back then. She had already seen her friends' kids wheezing and in the hospital for RSV. So she said yes and helped propel one of the most promising pharmaceuticals for RSV in decades.
JOE DOMACHOWSKE: RSV is the No. 1 reason why infants and young children are hospitalized not just in the U.S. but across the world.
MENTO: That's Dr. Joe Domachowske of Upstate Medical University Hospital in Syracuse. He's been working with the drugmaker AstraZeneca on a monoclonal antibody to prevent RSV. It's not a vaccine but what's known as passive immunization. And so in January 2015, Domachowske injected Cheryl's daughters with this experimental immune defense, making them the first two babies enrolled in the AstraZeneca study.
DOMACHOWSKE: So I started it myself. It was great fun.
MENTO: It was a significant moment in the battle against RSV. Back in the 1960s, one vaccine that was studied actually made kids get sicker. Two babies died. Decades later in the late '90s, a different monoclonal antibody came out. But Domachowske says it's restricted to high-risk babies like those with lung conditions or who were born prematurely. And it doesn't last very long.
DOMACHOWSKE: It has to be given monthly. And it's effective at preventing hospitalization, not effective at preventing infection.
MENTO: And that's where scientists had been stuck for years until a 2014 medical conference in Argentina. A speaker there dropped a massive discovery that a lot of RSV research focused on the wrong protein.
DOMACHOWSKE: You could hear a pin drop, and everyone is just sitting there staring with their mouths gaping open. It's like, this is why all of our work hasn't led to anything for decades. It was that impressive. And you could see the pharma people that were attending taking notes, calling their colleagues, saying, stop the - you know, stop the work.
MENTO: Fast-forward to now. Drugmaker Sanofi, which is partnering with AstraZeneca, says its trial shows the monoclonal antibody known as near nirsevimab is 75% effective at preventing severe infection throughout an RSV season. The drugmaker says the FDA is currently reviewing its application to get it approved in the U.S.
VANDANA MADHAVAN: This is a huge step.
MENTO: Dr. Vandana Madhavan is clinical director of pediatric infectious disease at Mass General for Children. She says nirsevimab is a significant development in the fight against RSV. That's because it's expected to be available for all babies facing their first season of RSV. And one shot should protect them for about five months.
MADHAVAN: The potential for a much larger effect on children is there. So it's really, you know, the next big step.
MENTO: Hi. What's your name?
CASSIDY MEANY: Cassidy.
MENTO: Cassidy.
STELLA MEANY: My name's Stella.
MENTO: Cassidy and Stella just turned 8. Cheryl says they never had complications from nirsevimab and didn't get RSV when they were tiny and vulnerable. And that's the point - delaying RSV infection in babies until they're strong enough to naturally and, hopefully, easily fight it off. Cheryl says she's proud of the role her girls played in this medical achievement.
MEANY: I mean, this matters. And this matters for kids everywhere, not just kids here.
MENTO: Nirsevimab is already OK'd in Europe. AstraZeneca and Sanofi say if the drug is approved in the U.S., it could be available by later this year. For NPR News, I'm Tarryn Mento in Syracuse. Transcript provided by NPR, Copyright NPR.
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