Emily Oster

7 min Read Emily Oster

Emily Oster

Bonus: FDA Releases Pfizer Data on Kids Vaccines

Emily Oster

7 min Read

This morning the FDA put out a release in advance of the October 26 ACIP meeting which will cover (among other things) vaccines for kids. The release contains the full Pfizer analysis of the Pfizer data for children. I know this is on a lot of our minds, so I wanted to dig into what they are reporting out in terms of trial details, safety and efficacy.

I wanted to get this out fast, so I didn’t tax my wonderful proofreader, Rina, for her help. As a result, we will be returning to the situation from several months ago in which my newsletters have a “charming” number of typos. Sorry!  (If you want to support the new, typo-free, situation please consider subscribing).

Okay, let’s go. I’m going to show and explain a bunch of their graphs and tables. Focusing on what we know about the trial, what they see in safety and what they see in efficacy.

Trial Details

To set the stage, here’s the simple table of information on what happened in the trial (I’m going to focus here on the Phase 2/3 trial data, which is the new information on which approval will be largely based). In this trial, Pfizer evaluated a dose of 10 micrograms. This is a third of the 30 microgram dose which is approved for adults and children over 12.

There are a total of 2285 individuals, of whom 1528 were randomized into getting the vaccine, 757 into the placebo. Nearly all of those randomized completed both doses and were followed up for at least a month after dose 2. (THANK YOU PEOPLE IN THE TRIAL).

and 

Not reported in this table are demographics, but they discuss them.

  • Race: 78.9% White, 6.5% Black, 6.0% Asian, 7% multiracial
  • Ethnicity: 21.1% Hispanic/Latino
  • Gender: 52.1% Male.
  • About 20% of both groups had comorbidities, of which asthma was the most common.

Safety

When we look at safety data, the FDA focuses on three things: local reactions, systematic reactions, and severe adverse events.

Local Reactions

Local reactions are both the most common and probably the ones we least worry about. 75% of the vaccinated participants had mild or moderate pain at the injection site. This is much higher than the placebo group (30%) although lower than a comparison groups of 16 to 25 year olds (85%). Pain in kids was also more likely to be mild (rather than moderate). The other somewhat common local reaction was redness (15 to 18% of kids, versus 6% in placebo).

Systemic Reactions

Of more interest and concern are more systemic reactions– fever, pain, fatigue, etc. The document repots this out separately by the first and second dose, and I’ve put both graphs below. They are a little dense, but actually pretty helpful.

Let’s focus on the first dose figure below. The report is trying to help us do two comparisons. The first is between the vaccinated kids and the placebo group. The second is between vaccinated kids and vaccinated older people (16 to 25). Both are useful comparisons.

Look at the fever comparison below. The red circle I’ve drawn compares the vaccinated kids to the placebo kids. 2.5% of vaccinated children had a fever after the first dose, versus 1.3% of the placebo group. The blue circle compares vaccinated kids to vaccinated young adults. 2.5% of vaccinated children had a fever, versus 7.3% of vaccinated young adults. (You can also do the double comparison — placebo reactions are similar in the two groups).

We conclude that fever is more likely in those who are vaccinated, although children have a lower rate of this side effect than young adults. You can do a similar analysis across all of the groups. In general, comparing vaccinated kids to the placebo, there are relatively few side effects which are more common in the vaccinated group. For example: 22% of the vaccinated kids report headache after the first dose, but so do 24% of the placebo!  If you squint, maybe muscle pain shows up as slightly more likely, but the increase is only about 2.3% so it’s hard to tell if this is even significant.

Very consistently we observe that the side effects are more severe for older groups. This conclusion holds also for dose 2 (see second graph below). There, however, we do see slightly higher side effects in the vaccinated group of children — more fatigue, headache, chills, fever. This is consistent with the generally higher rates of side effects for everyone with the second dose.

Broadly, I think these results look excellent for the vaccine.

Serious Adverse Effects

In both the vaccinated and placebo groups, some adverse events were reported. The rates, however, were similar in the two groups. Of the1518 vaccinated children, 3 reported severe adverse events; this is compared to 1 of the 750 kids in the placebo group. However, these were not judged to be related to the vaccine (example: upper limb fracture).

The FDA also asked for an additional month of follow-up, and there were none. Notably, there were no cases of myocarditis in this sample, which is a concern in slightly older children (although is rare there, as well). Broadly, this is excellent news. Here is where Pfizer lands on safety:

Phase 2/3 data from approximately 2250 children 5 to <12 years of age with a follow-up time of at least 2 months after Dose 2 showed BNT162b2 at 10 µg was safe and well-tolerated. (from report, p. 40)

Efficacy

The main efficacy results here rely on “immunobridging”. A subset of participants in the study were evaluated for antibody levels. Efficacy relies on observing an antibody response at a sufficient level, in this case comparable to the response seen in those 16 to 25.

This comparison is done for 264 children, compared to 253 individuals 16 to 25. The children got the 10 microgram dose, adults got the 30 micrograms. Antibody titer measures were 1197.6 for the child sample on average, 1146.5 for the older group. 99.2% of each group showed evidence of immune response. Conclusion: similar immune response.

In addition, there is a little bit of data on efficacy from actual SARS-COV-2 infection. I’ve put in Table 13 below. The sample is slightly smaller because they focus on kids without evidence of prior infection. Of these, 3 of the 1273 vaccinated children had evidence of COVID infection, versus 16 of the 663 placebo group. This translates to 90% efficacy. Which is so good!  There is also a nice graph showing how incidence evolves in the groups after vaccination.

Four things of note.

  1. This trial was run during the period in which the Delta variant dominated, which is good in terms of conclusions for the current setting.
  2. Overall the rates here are fairly low in both groups.
  3. There were no documented infections in either group among children who had previous evidence of SARS-COV-2 infection.
  4. There were no severe COVID-19 cases in either group, consistent with the overall low risk for children.

Bottom line on efficacy is that it looks good. Yes, the samples are small, but the protection against any illness seems really significant. And of course the antibody results are great.

What Happens Next?

The document ends with:

Taken together, the potential risks and benefits as assessed by the safety profile, efficacy, and immunogenicity of the 10 µg dose of BNT162b2, are balanced in favor of the potential benefits to prevent COVID-19 in children 5 to <12 years of age. (Page 71)

If the FDA agrees with Pfizer, they’ll move forward at the October 26 meeting, and then there is a second early November meeting for further approval. Earliest day for shot in arms is after that. I’ll be there, especially with these data in hand.

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Milestones. We celebrate them in pregnancy, in parenting, and they’re a fun thing to celebrate at work too. Just a couple years ago I couldn’t have foreseen what this community would grow into. Today, there are over 400,000 of you here—asking questions, making others feel seen wherever they may be in their journey, and sharing information that supports data > panic. 

It has been a busy summer for the team at ParentData. I’d love to take a moment here to celebrate the 400k milestone. As I’ve said before, it’s more important than ever to put good data in the hands of parents. 

Share this post with a friend who could use a little more data, and a little less parenting overwhelm. 

📷 Me and my oldest, collaborating on “Expecting Better”

Milestones. We celebrate them in pregnancy, in parenting, and they’re a fun thing to celebrate at work too. Just a couple years ago I couldn’t have foreseen what this community would grow into. Today, there are over 400,000 of you here—asking questions, making others feel seen wherever they may be in their journey, and sharing information that supports data > panic.

It has been a busy summer for the team at ParentData. I’d love to take a moment here to celebrate the 400k milestone. As I’ve said before, it’s more important than ever to put good data in the hands of parents.

Share this post with a friend who could use a little more data, and a little less parenting overwhelm.

📷 Me and my oldest, collaborating on “Expecting Better”
...

I spend a lot of time talking people down after they read the latest panic headline. In most cases, these articles create an unnecessary amount of stress around pregnancy and parenting. This is my pro tip for understanding whether the risk presented is something you should really be worrying about.

Comment “link” for an article with other tools to help you navigate risk and uncertainty.

#emilyoster #parentdata #riskmanagement #parentstruggles #parentingstruggles

I spend a lot of time talking people down after they read the latest panic headline. In most cases, these articles create an unnecessary amount of stress around pregnancy and parenting. This is my pro tip for understanding whether the risk presented is something you should really be worrying about.

Comment “link” for an article with other tools to help you navigate risk and uncertainty.

#emilyoster #parentdata #riskmanagement #parentstruggles #parentingstruggles
...

Here’s why I think you don’t have to throw away your baby bottles.

Here’s why I think you don’t have to throw away your baby bottles. ...

Drop your toddlers favorite thing right now in the comments—then grab some popcorn.

Original thread source: Reddit @croc_docs

Drop your toddlers favorite thing right now in the comments—then grab some popcorn.

Original thread source: Reddit @croc_docs
...

Just keep wiping.

Just keep wiping. ...

Dr. Gillian Goddard sums up what she learned from the Hot Flash  S e x  Survey! Here are some key data takeaways:

🌶️ Among respondents, the most common s e x u a l frequency was 1 to 2 times per month, followed closely by 1 to 2 times per week
🌶️ 37% have found their sweet spot and are happy with the frequency of s e x they are having
🌶️ About 64% of respondents were very or somewhat satisfied with the quality of the s e x they are having

Do any of these findings surprise you? Let us know in the comments!

#hotflash #intimacy #midlifepleasure #parentdata #relationships

Dr. Gillian Goddard sums up what she learned from the Hot Flash S e x Survey! Here are some key data takeaways:

🌶️ Among respondents, the most common s e x u a l frequency was 1 to 2 times per month, followed closely by 1 to 2 times per week
🌶️ 37% have found their sweet spot and are happy with the frequency of s e x they are having
🌶️ About 64% of respondents were very or somewhat satisfied with the quality of the s e x they are having

Do any of these findings surprise you? Let us know in the comments!

#hotflash #intimacy #midlifepleasure #parentdata #relationships
...

Should your kid be in a car seat on the plane? The AAP recommends that you put kids under 40 pounds into a car seat on airplanes. However, airlines don’t require car seats.

Here’s what we know from a data standpoint:
✈️ The risk of injury to a child on a plane without a carseat is very small (about 1 in 250,000)
✈️ A JAMA Pediatrics paper estimates about 0.4 child air crash deaths per year might be prevented in the U.S. with car seats 
✈️ Cars are far more dangerous than airplanes! The same JAMA paper suggests that if 5% to 10% of families switched to driving, then we would expect more total deaths as a result of this policy. 

If you want to buy a seat for your lap infant, or bring a car seat for an older child, by all means do so! But the additional protection based on the numbers is extremely small.

#parentdata #emilyoster #flyingwithkids #flyingwithbaby #carseats #carseatsafety

Should your kid be in a car seat on the plane? The AAP recommends that you put kids under 40 pounds into a car seat on airplanes. However, airlines don’t require car seats.

Here’s what we know from a data standpoint:
✈️ The risk of injury to a child on a plane without a carseat is very small (about 1 in 250,000)
✈️ A JAMA Pediatrics paper estimates about 0.4 child air crash deaths per year might be prevented in the U.S. with car seats
✈️ Cars are far more dangerous than airplanes! The same JAMA paper suggests that if 5% to 10% of families switched to driving, then we would expect more total deaths as a result of this policy.

If you want to buy a seat for your lap infant, or bring a car seat for an older child, by all means do so! But the additional protection based on the numbers is extremely small.

#parentdata #emilyoster #flyingwithkids #flyingwithbaby #carseats #carseatsafety
...

SLEEP DATA 💤 PART 2: Let’s talk about naps. Comment “Link” for an article on what we learned about daytime sleep!

The first three months of life are a chaotic combination of irregular napping, many naps, and a few brave or lucky souls who appear to have already arrived at a two-to-three nap schedule. Over the next few months, the naps consolidate to three and then to two. By the 10-to-12-month period, a very large share of kids are napping a consistent two naps per day. Over the period between 12 and 18 months, this shifts toward one nap. And then sometime in the range of 3 to 5 years, naps are dropped. What I think is perhaps most useful about this graph is it gives a lot of color to the average napping ages that we often hear. 

Note: Survey data came from the ParentData audience and users of the Nanit sleep monitor system. Both audiences skew higher-education and higher-income than the average, and mostly have younger children. The final sample is 14,919 children. For more insights on our respondents, read the full article.

SLEEP DATA 💤 PART 2: Let’s talk about naps. Comment “Link” for an article on what we learned about daytime sleep!

The first three months of life are a chaotic combination of irregular napping, many naps, and a few brave or lucky souls who appear to have already arrived at a two-to-three nap schedule. Over the next few months, the naps consolidate to three and then to two. By the 10-to-12-month period, a very large share of kids are napping a consistent two naps per day. Over the period between 12 and 18 months, this shifts toward one nap. And then sometime in the range of 3 to 5 years, naps are dropped. What I think is perhaps most useful about this graph is it gives a lot of color to the average napping ages that we often hear.

Note: Survey data came from the ParentData audience and users of the Nanit sleep monitor system. Both audiences skew higher-education and higher-income than the average, and mostly have younger children. The final sample is 14,919 children. For more insights on our respondents, read the full article.
...

Happy Father’s Day to the Fathers and Father figures in our ParentData community! 

Tag a Dad who this holiday may be tricky for. We’re sending you love. 💛

Happy Father’s Day to the Fathers and Father figures in our ParentData community!

Tag a Dad who this holiday may be tricky for. We’re sending you love. 💛
...

“Whilst googling things like ‘new dad sad’ and ‘why am I crying new dad,’ I came across an article written by a doctor who had trouble connecting with his second child. I read the symptoms and felt an odd sense of relief.” Today we’re bringing back an essay by Kevin Maguire of @newfatherhood about his experience with paternal postpartum depression. We need to demystify these issues in order to change things for the better. Comment “Link” for a DM to read his full essay.

#parentdata #postpartum #postpartumdepression #paternalmentalhealth #newparents #emilyoster

“Whilst googling things like ‘new dad sad’ and ‘why am I crying new dad,’ I came across an article written by a doctor who had trouble connecting with his second child. I read the symptoms and felt an odd sense of relief.” Today we’re bringing back an essay by Kevin Maguire of @newfatherhood about his experience with paternal postpartum depression. We need to demystify these issues in order to change things for the better. Comment “Link” for a DM to read his full essay.

#parentdata #postpartum #postpartumdepression #paternalmentalhealth #newparents #emilyoster
...

What does the data say about children who look more like one parent? Do they also inherit more character traits and mannerisms from that parent? Let’s talk about it 🔎

#emilyoster #parentdata #parentingcommunity #lookslikedaddy #lookslikemommy

What does the data say about children who look more like one parent? Do they also inherit more character traits and mannerisms from that parent? Let’s talk about it 🔎

#emilyoster #parentdata #parentingcommunity #lookslikedaddy #lookslikemommy
...

SLEEP DATA 💤 We asked you all about your kids’ sleep—and got nearly 15,000 survey responses to better understand kids’ sleep patterns. Comment “Link” for an article that breaks down our findings!

This graph shows sleeping location by age. You’ll notice that for the first three months, most kids are in their own sleeping location in a parent’s room. Then, over the first year, this switches toward their own room. As kids age, sharing a room with a sibling becomes more common. 

Head to the newsletter for more and stay tuned for part two next week on naps! 🌙

#parentdata #emilyoster #childsleep #babysleep #parentingcommunity

SLEEP DATA 💤 We asked you all about your kids’ sleep—and got nearly 15,000 survey responses to better understand kids’ sleep patterns. Comment “Link” for an article that breaks down our findings!

This graph shows sleeping location by age. You’ll notice that for the first three months, most kids are in their own sleeping location in a parent’s room. Then, over the first year, this switches toward their own room. As kids age, sharing a room with a sibling becomes more common.

Head to the newsletter for more and stay tuned for part two next week on naps! 🌙

#parentdata #emilyoster #childsleep #babysleep #parentingcommunity
...

Weekends are good for extra cups of ☕️ and listening to podcasts. I asked our team how they pod—most people said on walks or during chores. What about you?

Comment “Link” to subscribe to ParentData with Emily Oster, joined by some excellent guests.

#parentdata #parentdatapodcast #parentingpodcast #parentingtips #emilyoster

Weekends are good for extra cups of ☕️ and listening to podcasts. I asked our team how they pod—most people said on walks or during chores. What about you?

Comment “Link” to subscribe to ParentData with Emily Oster, joined by some excellent guests.

#parentdata #parentdatapodcast #parentingpodcast #parentingtips #emilyoster
...

Humility. That’s why. That’s the whole reason.

#emilyoster #secondbaby #parentingjokes #parentinghumor

Humility. That’s why. That’s the whole reason.

#emilyoster #secondbaby #parentingjokes #parentinghumor
...

Bug season is upon us. Besides annoyance, this can bring up safety concerns, particularly with ticks. They are carriers of diseases, most notably Lyme disease. So what’s the best course of action?

Prevention is key! I suggest:
⭐ Regular tick checks
⭐ Using bug sprays with DEET 
⭐ Wearing long sleeves and pants in the woods

Some parents worry about DEET, but repellants with up to 30% DEET are recommended by both the CDC and AAP. The data says you’re in the clear, so go for it. Enjoy your summer!

#parentdata #emilyoster #tickseason #bugbites #bugspray

Bug season is upon us. Besides annoyance, this can bring up safety concerns, particularly with ticks. They are carriers of diseases, most notably Lyme disease. So what’s the best course of action?

Prevention is key! I suggest:
⭐ Regular tick checks
⭐ Using bug sprays with DEET
⭐ Wearing long sleeves and pants in the woods

Some parents worry about DEET, but repellants with up to 30% DEET are recommended by both the CDC and AAP. The data says you’re in the clear, so go for it. Enjoy your summer!

#parentdata #emilyoster #tickseason #bugbites #bugspray
...