Today’s YLE newsletter talked about why Pfizer’s <5 year old trial failed, which is an interesting, but one that doesn’t have an obvious answer at this point.
The thing I thought was interesting, though, relates to the difference between the Pfizer and Moderna vaccines. I had more or less viewed them interchangeably, although I never quite understood the different dosages. Today’s newsletter framed it as an intentional choice, which could ultimately explain why Pfizer’s trial for young kids failed.
(This all seems kind of straightforward in hindsight, so may not be news to anyone here.)
Basically, if you’re a drug manufacturer, you’ve got to accomplish two things with a given vaccine:
generate a meaningful immune response
limit the side effects
But these two goals can be in conflict, particularly in terms of dosages - a higher dosage is both more likely to generate an immune response AND generate side effects. So you need to figure out where on that continuum between efficacy and safety you are aiming for.
The newsletter frames Moderna and Pfizer as having different targets on that continuum, both of which are reasonable:
Moderna is aggressive, favoring efficacy, and aims for the highest possible dosage without incurring too much side effect risk.
Pfizer is conservative, favoring safety, and aims for the lowest possible dosage that still yields meaningful benefits.
[Side note: This is similar to the two ways of framing optimal investing - aiming for the highest possible return at a given level of risk vs. aiming for the lowest possible risk to achieve a given return]
So Pfizer’s vaccine fails to get authorization not because of side effects, but because it doesn’t demonstrate sufficient efficacy. On the flip side, Moderna’s vaccine could also fail, but for a different reason - plenty of efficacy, but increased risk of myocarditis associated with the higher dosage.
Alright, so where the fuck is Moderna’s pediatric data? Where’s the fuckin’ data, Moderna? Where’s the fuckin’ data?
They’re still not approved for even under 18, ya? Like, ok, I’m mad at Pfizer for whiffing on < 5, but fuck Moderna for not changing course after still not being approved for < 18 after this long.
The Moderna COVID-19 vaccine is authorized for adults over the age of 18 years and is waiting for a response to its June application for children aged 12 through 17.
Although, echoing my original post, I guess it would make sense that if the FDA requested both Pfizer and Moderna to expand their trials specifically because of side effects, that Moderna (with the higher dosage) would be the one more likely to be in jeopardy.
As for younger kids, maybe another month or two?
For the Moderna COVID-19 vaccine, the right dose in kids under 6 appears to be just 25% of the adult dose, Dr. Bill Hartman, principal investigator for UW Health’s KidCOVE Moderna pediatric vaccine trial, told TODAY. In children ages 6 to 11, the company deemed a 50 microgram dose effective, which is half the size of the adult dose.
Hartman anticipates that Moderna will be able to begin interpreting data about its vaccine in younger kids in mid-January and the company will decide whether or not to pursue an emergency use authorization at that time.
Although the question here is whether drug companies will be allowed to skip age groups. This is something that the newsletter addressed - that the trials for younger kids are basically assuming some relationships between the efficacy already found in older individuals and the efficacy in younger indviduals. It might be the case that you can’t skip “generations” and still apply that logic. That is, Pfizer’s trial was actually successful for the <2 year old group, but because it wasn’t successful for the 2-5 year old group, they can’t get authorization for the younger group either. This is probably unclear because I really don’t understand it at all, and it seemed more like speculation in the newsletter than known fact.
I mean, Pfizer’s failure seems like a concentration effect. A small dose in very small bodies was concentrated enough, but in somewhat larger bodies the same dose wasn’t enough to generate the same response. Pfizer’s decision to go with a 3rd tiny dose seems dubious, more like a Hail Mary to try and salvage a failed study for less money than the most likely thing to work.
I’m back at my parents’ place for Christmas. Everyone is vaxxed and boosted but I’m still pretty sure we’re just spraying firehoses of covid all over each other.
Are there more colds floating around this year in addition to Covid? I hardly ever get sick but in the last few months I’ve had two colds lasting like 10+ days, but always testing negative for covid. Very strange.
Sucks that the test results show up as invalid in my app because they aren’t accepted as proof of infectivity anymore. Can be very misleading and anxiety-inducing for people like me who didn’t know that initially.
Literally the best thing about COVID is not having my mom bitch about us not going to visit (we live over a thousand miles apart and this is not an accident) for the holidays. We wouldn’t have anyway, but it’s an impossible to deal with excuse.
As for the medical staff being overwhelmed issue my wife quit her job three weeks ago. I doubt she’ll ever take another nursing job unless we are in very dire straights financially and there are literally no other options. At this point the American people deserve for the health system to fully collapse on them for allowing it to continue like this for so long. May we all run good medically this winter because it sure looks like we’re going to need to… but let’s not kid ourselves many of us (absolutely including me) have needed to run good medically to not be totally fucked our whole lives.
I can’t read that NY Times article. What exactly is the military going to do? Containment of Omicron is not achievable, the ways they can help are to a) somehow get boosters in arms faster or b) use their resources to somehow assist overrun hospitals. I’m not sure how they can do either fast enough, but I don’t really know anything about it. If they had started when we first heard about Omicron, I would be more confident. The WHO designated it a variant of concern on Nov 26, if the military had starting doing stuff then I could see the potential that they would really help. But trying to chase Covid new “threat” variants a month after they’re detected seems pretty futile. I think all the help will arrive right after spread has done most of it’s damage.
Assisting hospitals, but I assume adding military personnel to hospitals can at least expand capacity reasonably quickly while someone getting vaxxed today isn’t really going to have much protection for like six weeks.
For the rapid tests completely agree. Good to have this set up to control ongoing spread, but expect this wave has peaked by the time that gets up and running.
These aren’t “bad” actions since it seems like COVID control measures are necessary for at least the medium-term (recent UK report estimated some measures will be needed for a decade or more), but seems wholly inadequate for this fight. N95 to every household every week would have been useful too, but also probably too late for this surge.