New RSV Prevention Drug for Babies and Toddlers

Emily Oster

8 min Read Emily Oster

Emily Oster

New RSV Prevention Drug for Babies and Toddlers

And who should consider getting it

Emily Oster

8 min Read

It’s almost September, which means cooler running weather, kids finally getting back to school, and … respiratory viruses. Respiratory viruses tend to peak in the fall and winter, when people spend more time indoors in crowded venues. Last fall was especially bad — as I talked about then, an early RSV season overlapped with croup, and a post-COVID immunity debt made everything worse.

Fingers crossed that this fall will be back to our more “normal” pre-COVID patterns, but that still means a lot of illness. The three big concerns for the fall: COVID, the flu, and RSV. There are vaccines for both COVID and the flu, but until this season, there has not been any good way to prevent RSV.

This is unfortunate, because when we consider babies and small children, RSV is the most concerning of these big three. You can read a longer explainer on RSV here, but the bottom line is that infection presents a significant risk of hospitalization for young children, especially infants born preterm or children with respiratory conditions. There are an estimated 100 to 500 deaths among children from RSV each year.

In the past year, there have been three advances in RSV prevention. The first, which I talked about here, is a vaccine for adults over 65 (the other very vulnerable group outside of babies).

The second is the recommended use of the same vaccine for pregnant people. When given later in pregnancy, it protects infants in their first six months. On Monday, the FDA approved this use of the vaccine. If you want to understand more about this option for protecting your infant, go back to the earlier post on RSV vaccines. If you’re pregnant now, it could be a great option. One note is that some concerns have been raised about higher preterm birth with the vaccine, although differences across groups were not statistically significant in the trial. The FDA has asked the companies for follow-up monitoring on this option.

The third advance, the topic for today, is the approval of a drug to prevent RSV in babies and toddlers.

Overview

Several weeks ago, the FDA approved a new drug, called Beyfortus, to prevent RSV in infants and vulnerable toddlers. You can see the full FDA press release here. The medication is a monoclonal antibody — basically, it provides protection by delivering RSV antibodies directly to the patient. This drug isn’t a vaccine, but it is delivered in a shot. The drug is approved for newborns and infants entering their first RSV season (i.e. those who were not born last fall) and for kids up to 24 months who have some risk factors (for example, those who were preterm or have had lung issues in the past).

It’s worth pausing on the reason for this particular designation. RSV is ubiquitous. The vast majority of people will get it many times in their lives, and for most older children and adults, it presents as a mild cold. The groups who are at risk for more serious illness are babies under 1, older adults, and individuals with lung conditions.

The goal of RSV prevention is to prevent RSV in these more vulnerable groups. In the case of older adults, the idea is that they will get the RSV vaccine each year, similar to how people get the flu vaccine now. For babies, the idea is to give them the RSV drug preventionin at least their first year to prevent infection during the most vulnerable period. It is likely that these children will get RSV for the first time in their second RSV season. They will not avoid it indefinitely, but they will get it for the first time when they are less likely to have serious illness.

With this background, we can frame the question. For parents of children who were born after last fall, who have not yet had RSV: Should you get them this treatment? Let’s look to the trial data.

Trial data on efficacy

The first trial of this medication was published in 2020 in the New England Journal of Medicine, based on data from the 2016-2017 RSV season. The population in the trial was infants born between 29 and 35 weeks of gestation, a group known to be at high risk for complications from RSV. The trial included 1,453 infants, of whom two-thirds were given the drug (here, under its generic name nirsevimab) and a third of whom got a placebo. As usual in this type of trial, which group people were in was hidden to the doctors and to the patients (“double blind”).

The group that got the drug had significantly less RSV. There was a 70% reduction in any RSV needing medical attention and a 78% reduction in RSV hospitalization. Four percent of the placebo group were hospitalized with RSV, versus 0.8% of the treated group.

This is a very good efficacy profile. In terms of safety, there were no notable differences in adverse events across the two groups. There were three deaths in the placebo group and two in the treated group, although none of these were thought to be related to the drug.

This first trial focused on the highest-risk preterm infants. A second trial, published in 2022, used a very similar design but recruited infants born at 35 weeks or after. Most of the infants in the trial (86%) were born at or after 37 weeks, so considered full-term. This population is lower-risk overall, but there was still strong evidence of the efficacy of the treatment.

The chance of any RSV requiring medical attention was reduced by 74%, and the chance of hospitalization was reduced by 62%. It is worth noting that this second efficacy figure is based on much smaller numbers of hospitalizations (six in one group, eight in the other), so it is not statistically precise.

In terms of safety: the overall share of infants with adverse events were similar in the two groups. There were three deaths in the treatment group and none in the placebo group, but on detailed investigation it did not appear likely that any of these deaths were related to the drug

These main trials focused on the category of “infants in their first RSV season.” A third trial, also published in a short piece in the NEJM, focused on the safety of this drug in a population of older children who were high-risk (in this case, with congenital heart disease). This trial tested nirsevimab against the existing option for high-risk infants, a drug called palivizumab that requires monthly dosing during the season. The efficacy of the drugs was similar (as expected), and the safety profile also looked similar (which was the point of the trial). Sadly, there were also six deaths in this trial — five in the treated group and one in the placebo group — but they were not thought to be related to the vaccination.

(One question you might ask: How would they know if deaths were related? The answer is that there is an extremely detailed process in these trials for following up on any adverse event, especially serious ones, to get all the possible information in order to evaluate whether it might have been related to the drug.)

The FDA conclusion from the trial data was that this is an option that shows great efficacy in preventing RSV in infants, and it appears safe as an option for medically compromised older children. This latter group already has access to the other option (palivizumab), but the newer option seems to deliver the same protection in a single dose.

What’s next?

The manufacturer of Beyfortus has indicated that it should be available ahead of this winter’s RSV season. You’re likely to hear about it from your pediatrician, either at a fall well-child visit or in direct outreach.

Like with all new medications, there will be people who are eager and excited to get this immediately, and there will be those who feel more cautious. This medication has been approved in Europe for a year already, and the trial data is compelling, but drug treatments for babies are a fraught choice for many. And this is a case, unlike some, where the value of treatment is really to the individual child. We aren’t urging people to vaccinate their babies to protect older people; it’s an urge to protect the babies themselves. Which really does make this an individual family choice.

What I will say here about the choice is that RSV is dangerous for a lot of babies, and the efficacy numbers on this drug are extremely good. If you have an infant — especially one born preterm — going into this first RSV season, I would urge you to get them this shot.

Note: This piece was updated at 8:55 AM on 8/24 to correct the error in referring to this new drug as a vaccine. We regret the error.

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The AAP’s guidelines recommend sleeping in the same room as your baby “ideally for the first six months.” However, the risk of SIDS is dramatically lower after four months, and the evidence in favor of the protective effect of room sharing is quite weak (both overall and even more so after four months). There is also growing evidence that infants who sleep in their own room by four months sleep better at four months, better at nine months, and even better at 30 months.

With this in mind, it’s worth asking why this recommendation continues at all — or at least why the AAP doesn’t push it back to four months. They say decreased arousals from sleep are linked to SIDS, which could mean that babies sleeping in their own room is risky. But this link is extremely indirect, and they do not show direct evidence to support it.

According to the data we have, parents should sleep in the same room as a baby for as long as it works for them! Sharing a room with a child may have negative impacts on both child and adult sleep. We should give families more help in navigating these trade-offs and making the decisions that work best for them.

#emilyoster #parentdata #roomsharing #sids #parentingguide

The AAP’s guidelines recommend sleeping in the same room as your baby “ideally for the first six months.” However, the risk of SIDS is dramatically lower after four months, and the evidence in favor of the protective effect of room sharing is quite weak (both overall and even more so after four months). There is also growing evidence that infants who sleep in their own room by four months sleep better at four months, better at nine months, and even better at 30 months.

With this in mind, it’s worth asking why this recommendation continues at all — or at least why the AAP doesn’t push it back to four months. They say decreased arousals from sleep are linked to SIDS, which could mean that babies sleeping in their own room is risky. But this link is extremely indirect, and they do not show direct evidence to support it.

According to the data we have, parents should sleep in the same room as a baby for as long as it works for them! Sharing a room with a child may have negative impacts on both child and adult sleep. We should give families more help in navigating these trade-offs and making the decisions that work best for them.

#emilyoster #parentdata #roomsharing #sids #parentingguide
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Watch the full segment at the link in my bio 🔗

#tamronhall #tamronhallshow #emilyoster #parentingsupport #workingparents

It was an absolute pleasure to be featured on the @tamronhallshow! We talked about all things data-driven parenting and, in this clip, what I call the plague of secret parenting. To balance having a career and having a family, we can’t hide the fact that we’re parents. If mothers and fathers at the top can speak more openly about child-care obligations, it will help us all set a new precedent.

Watch the full segment at the link in my bio 🔗

#tamronhall #tamronhallshow #emilyoster #parentingsupport #workingparents
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My guest on this episode, @everodsky, has come up with a solution here, or at least a way for us to recognize the problem and make our own solutions. I’ve wanted to speak with Eve for ages, since I read her book Fair Play. We had a great conversation about the division of household labor, one I think you’ll get a lot out of!

Listen and subscribe to ParentData with Emily Oster in your favorite podcast app 🎧

#emilyoster #parentdata #parentdatapodcast #parentingpodcast #householdtips #fairplay #invisiblelabor

Invisible labor. It’s the work — in our households especially — that has to happen but that no one sees. It’s making the doctor’s appointment, ensuring birthday cards are purchased, remembering the milk.

My guest on this episode, @everodsky, has come up with a solution here, or at least a way for us to recognize the problem and make our own solutions. I’ve wanted to speak with Eve for ages, since I read her book Fair Play. We had a great conversation about the division of household labor, one I think you’ll get a lot out of!

Listen and subscribe to ParentData with Emily Oster in your favorite podcast app 🎧

#emilyoster #parentdata #parentdatapodcast #parentingpodcast #householdtips #fairplay #invisiblelabor
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Good news: fancier vitamins are not better.  Folic acid is the most important prenatal ingredient. Iron (with vitamin C) and DHA are also nice to have. Other included ingredients have only weak or no evidence to support their use. (If you do not consume animal products, add B12, plus a few others depending on your diet.)

Vitamins are just vitamins. Any prenatal vitamin that contains these is enough. 

Comment “Link” for a DM to an article with everything you need to know about prenatal vitamins.

#emilyoster #parentdata #prenatalvitamins #pregnancydiet #pregnancytips

Prenatal vitamins 💊 If there is any product that seems designed to prey on our fears, it’s this one. You’re newly pregnant and you want to do it right. Everyone agrees you need prenatal vitamins, so you get them. But do you want to be that person who just… buys the generic prenatal vitamins?

Good news: fancier vitamins are not better. Folic acid is the most important prenatal ingredient. Iron (with vitamin C) and DHA are also nice to have. Other included ingredients have only weak or no evidence to support their use. (If you do not consume animal products, add B12, plus a few others depending on your diet.)

Vitamins are just vitamins. Any prenatal vitamin that contains these is enough.

Comment “Link” for a DM to an article with everything you need to know about prenatal vitamins.

#emilyoster #parentdata #prenatalvitamins #pregnancydiet #pregnancytips
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#parentdata #emilyoster #newborncare #parentingadvice #parentingtips

When it comes to introducing your newborn to the world, timing matters. It’s a good idea to minimize germ exposure in the first 6-8 weeks; after that, it’s inevitable and, very likely, a good idea! This doesn’t mean you need to be trapped inside. The most significant exposure risks are from seeing other people at home — family, etc. These interactions are not infinitely risky, but they do pose more risk than a walk or a trip to the grocery store, since they involve closer interaction. Think simple and make sure everyone is washing their hands before holding the baby. 💛

#parentdata #emilyoster #newborncare #parentingadvice #parentingtips
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The first edition of Hot Flash is out now! Comment “Link” for a DM to learn more about the late-reproductive stage.

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🔥 Hot Flash from ParentData is a weekly newsletter on navigating your health and hormones in the post-reproductive years. Written by Dr. Gillian Goddard, Hot Flash provides all of the information you need to have a productive, evidence-based conversation about hormonal health with your doctor.

#emilyoster #parentdata #hotflash #perimenopause #womenshealth

The first edition of Hot Flash is out now! Comment “Link” for a DM to learn more about the late-reproductive stage.

There are times when we expect hormonal shifts. Our reproductive lives are bookended by puberty and menopause. We discuss those changes often because they are definitive and dramatic — a first period is something many of us remember clearly. But between ages 13 and 53, our hormones are changing in more subtle ways. During the late-reproductive stage (in your 40s), you can expect a lot of changes in your menstrual cycle, including the length and symptoms you experience throughout. It’s an important time in our lives that is often overlooked!

🔥 Hot Flash from ParentData is a weekly newsletter on navigating your health and hormones in the post-reproductive years. Written by Dr. Gillian Goddard, Hot Flash provides all of the information you need to have a productive, evidence-based conversation about hormonal health with your doctor.

#emilyoster #parentdata #hotflash #perimenopause #womenshealth
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Now tell me in the comments: what’s a parenting move you’ve made recently that feels right to you?

#parentingcommunity #parentingsupport #parentingquotes #emilyoster #parentdata

There are plenty of reels telling you how to parent. Plenty of panic headlines saying that “studies show” what’s best for your kid. Even good data, from a trusted source, can send us into a spiral of comparison. But I want you to remember that no one knows your kid better than you. It’s important to absorb the research, but only you will know the approach that works best for you and your child. 💙

Now tell me in the comments: what’s a parenting move you’ve made recently that feels right to you?

#parentingcommunity #parentingsupport #parentingquotes #emilyoster #parentdata
...

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Listen and subscribe to ParentData with Emily Oster in your favorite podcast app 🎧

#parentdata #parentdatapodcast #emilyoster #emilynagoski #comeasyouare #cometogether #longtermrelationship #intimacy #relationships

Let’s talk about sex (after) baby! Today on the podcast, I was lucky enough to speak with @enagoski about her new book on sexual connection in long-term relationships. Especially after having kids, this is something many people struggle with. Emily tells us to stop worrying about what’s “normal” and focus on pleasure in its many forms.

Listen and subscribe to ParentData with Emily Oster in your favorite podcast app 🎧

#parentdata #parentdatapodcast #emilyoster #emilynagoski #comeasyouare #cometogether #longtermrelationship #intimacy #relationships
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Ever wondered if you can safely use leftover baby formula? 🍼 The CDC says to throw out unused formula immediately because of the risk of bacterial growth. However, research suggests that bacterial concentrations do not appreciably increase after 3, 12, or even 24 hours at refrigerator temperatures. Good news! This means there’s not a strong data-based reason to throw out formula right away if you store it in the fridge.

Comment “Link” for a DM to an article on another common formula question: should you throw away old formula powder?

#emilyoster #parentdata #babyformula #babyfeeding #parentingstruggles

Ever wondered if you can safely use leftover baby formula? 🍼 The CDC says to throw out unused formula immediately because of the risk of bacterial growth. However, research suggests that bacterial concentrations do not appreciably increase after 3, 12, or even 24 hours at refrigerator temperatures. Good news! This means there’s not a strong data-based reason to throw out formula right away if you store it in the fridge.

Comment “Link” for a DM to an article on another common formula question: should you throw away old formula powder?

#emilyoster #parentdata #babyformula #babyfeeding #parentingstruggles
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#emilyoster #parentdata #parentingtips #parentingadvice #newparents #parentingcommunity

What’s the most important piece of advice for new parents? Here’s one answer, but I want to hear from you! Share your suggestions in the comments ⬇️

#emilyoster #parentdata #parentingtips #parentingadvice #newparents #parentingcommunity
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What's in the bag of a Vagina Economist? 👀 Someone please tell me this looks familiar to you.

What`s in the bag of a Vagina Economist? 👀 Someone please tell me this looks familiar to you. ...

Comment ”link” for a DM to learn more about tongue ties 🔗

Breastfeeding is often difficult, especially at the start. For babies with tongue ties, many infants (and their moms) struggle to get the hang of a good latch. This can lead to painful nipples and to inefficient feeding, and then low weight gain.

So what does the data say about the increasingly common practice of cutting tongue-ties in infants to improve breastfeeding success? Several weeks ago, @nytimes published a long and quite scary article on this topic.

After diving into the data, here is what I found. There is limited evidence that frenotomy procedures improve breastfeeding efficacy and the harms of the procedure are minimal. Many women do report that it alleviates pain and helps them with breastfeeding. However, it should not be a first-line treatment for breastfeeding problems.

#parentdata #emilyoster #tonguetie #tonguetiebabies #breastfeedingsupport

Comment ”link” for a DM to learn more about tongue ties 🔗

Breastfeeding is often difficult, especially at the start. For babies with tongue ties, many infants (and their moms) struggle to get the hang of a good latch. This can lead to painful nipples and to inefficient feeding, and then low weight gain.

So what does the data say about the increasingly common practice of cutting tongue-ties in infants to improve breastfeeding success? Several weeks ago, @nytimes published a long and quite scary article on this topic.

After diving into the data, here is what I found. There is limited evidence that frenotomy procedures improve breastfeeding efficacy and the harms of the procedure are minimal. Many women do report that it alleviates pain and helps them with breastfeeding. However, it should not be a first-line treatment for breastfeeding problems.

#parentdata #emilyoster #tonguetie #tonguetiebabies #breastfeedingsupport
...

Tag a friend who needs to hear this 💛 For many choices in parenting, there is no one right answer. We can use research and data to make informed decisions, but ultimately, it won’t tell you what to do. Only you can decide what will be best for your kids and your family.

I’m here to remind you to take a deep breath and trust yourself. I’ll be here to support you along the way. 

Thank you to everyone who submitted videos, including:
@sarah.consoli
@jess_lynn627
@nicolevandenwills
@thedrblair
@ncbenedict29
@haleycimini
@iamkellysnodgrass
@calesse_smith
@garnet__gordon
@jencoopgaiser87
@danigirl18c
@jamielundergreen
@carly_comber
@thecelebratingmama
@emilyannbynum
@eeliz413

#emilyoster #parentdata #parentingadvice #parentingsupport #parentingquotes

Tag a friend who needs to hear this 💛 For many choices in parenting, there is no one right answer. We can use research and data to make informed decisions, but ultimately, it won’t tell you what to do. Only you can decide what will be best for your kids and your family.

I’m here to remind you to take a deep breath and trust yourself. I’ll be here to support you along the way.

Thank you to everyone who submitted videos, including:
@sarah.consoli
@jess_lynn627
@nicolevandenwills
@thedrblair
@ncbenedict29
@haleycimini
@iamkellysnodgrass
@calesse_smith
@garnet__gordon
@jencoopgaiser87
@danigirl18c
@jamielundergreen
@carly_comber
@thecelebratingmama
@emilyannbynum
@eeliz413

#emilyoster #parentdata #parentingadvice #parentingsupport #parentingquotes
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Congratulations on making it through another year of panic headlines! We’ve had some doozies this year, like aspartame causing cancer and the perils of white noise, but these headlines are very often based on poor data. Correlation does not equal causation. There will certainly be more panic headlines in 2024, but ParentData is here to debunk them for you.

#emilyoster #parentdata #happynewyear2024 #panicheadline #datadriven

Congratulations on making it through another year of panic headlines! We’ve had some doozies this year, like aspartame causing cancer and the perils of white noise, but these headlines are very often based on poor data. Correlation does not equal causation. There will certainly be more panic headlines in 2024, but ParentData is here to debunk them for you.

#emilyoster #parentdata #happynewyear2024 #panicheadline #datadriven
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