The second pregnancy for Cheryl Meany quickly turned from joyful to terrifying. She'd gone from struggling to get pregnant, to the exciting news she was carrying twins to frequent worries from doctors about the twins' health.
So she needed a moment to process when her husband proposed enrolling the soon-to-be-born babies in an experimental study for an RSV immunization.
"It took me aback, like 'What are you even talking about? I don’t even know what you’re asking me right now,'" Meany said.
That was back in 2014, several years before the recent RSV surge overwhelmed hospitals across the country. But Meany was worried about it back then after seeing multiple friends with kids in the hospital for the illness — up to 80,000 children under five are admitted for RSV each year. So Meany said yes, and her decision helped move forward one of the most promising RSV preventative tools in decades.
"RSV is the number one reason why infants and young children are hospitalized, not just in the US, but across the world," said Dr. Joseph Domachowske, a pediatrics infectious disease specialist at Upstate Medical University.
Domachowske led the hospital's previous COVID-19 vaccine trial for kids. But for years, he’s worked with AstraZeneca on a monoclonal antibody that's a ready-made immune defense against RSV.
With Meany's agreement, he injected her daughters with it in January 2015, making them the first babies in the world ever to receive it.
“I started it myself, it was great fun," Domachowske said.
Domachowske, a Meany family friend, said immunizing the twin babies was a significant moment after researchers had struggled for years to find success. Back in the 1960s, a vaccine under study made kids sicker from RSV.
“It really charged up the wrong half of the immune system," Domachowske said.
Two babies died because of it.
Progress didn’t come until two decades later. In 1998, FDA OK’d a monoclonal antibody for premature and high-risk babies. But Domachowske said changing medical guidelines since then have severely limited eligibility, and, he said, its efficacy wasn't great.
"It has to be given monthly," Domachowske said. "And it's effective at preventing hospitalization, not effective at preventing infection.”
That’s where we’d been stuck for years until 2014, when Domachowsk attended a medical conference in Argentina. A featured speaker dropped a massive discovery that a lot of RSV research focused on the wrong protein.
“Everyone is sitting there staring with their mouths gaping open like, 'This is why all of our work hasn't led to anything for decades," Domachowske said. "It was that impressive. And you can see the pharma people that were attending, taking notes, calling their colleagues saying, 'Stop, stop the work.”
Not too long later, he injected Meany’s daughters with an improved monoclonal antibody, known as nirsevimab, that protects babies through an RSV season with one shot.
The twin girls, Cassidy and Stella, are now 8 years old and like to compete in ninja warrior contests—they race through obstacle courses that feature ladders, monkey bars and overturned Bosu balls.
Meany said the girls never had complications from the shot and never got RSV. But she said they did get a spot in medical history when AstraZeneca asked to use their photos for research papers.
“I think at that point, I was like, 'Wow, I mean, this matters, and this matters for kids everywhere, not just kids here,'” Meany said.
Domachowske said the girls likely got RSV in later seasons, but symptoms weren’t noticeable.
AstraZeneca said its third phase results showed its once dose was about 75% effective at preventing severe infection.
Domachowske expects a greenlight by spring and nirsevimab to be on available by the next RSV season in the fall. It has already been approved in Europe.
