10 ms·

Quarter-dose of Moderna Covid vaccine still rouses a big immune response

109 points by _Microft 5y ago

Synaesthesia 5y ago
This is great news for Africa which really needs vaccines right now. It's great that all this vaccine research is going on. But the inequality of access is a huge problem. Up to now Africa hasnt had a big wave of covid, but this 3rd wave has hit us really hard (and I know, Africa is not a country, I live in South Africa). What experts warned about might happen is happening now: because of insufficient vaccinations the Covid pandemic will stick around and mutate in poor countries.
- deleted 5y ago
  [deleted]
- afavour 5y ago
  This is one of the things that depresses me the most… rich countries don’t even need to be altruistic here. Be entirely selfish: send vaccines to worse off countries to cut down on the number of mutations that will inevitably arrive on your shores. The really depressing part is that the exact same logic applies to climate change, so I’m not exactly full of hope for the future right now.
  - makomk 5y ago
    It doesn't matter whether your justification for why this should happen is altruism or selfishness, the same problem remains: a vaccination program of the scale and speed we've already seen is literally unprecedented, it's astounding that everyone managed this much, and yet even with that incredible effort there still aren't the doses to vaccinate the planet any time in the imminent future let alone the on-the-ground infrastructure to deliver them everywhere - and even the rich, developed countries with the best vaccine rollouts out there probably haven't reached herd immunity before new variants made that impractical or even impossible with the current vaccines. This isn't that remarkable. Previous attempts to deal with respiratory disease pandemics using vaccines have proved pretty futile, even though it is a standard part of pandemic planning.
    - oezi 5y ago
      I think the remarkable thing is that vaccine development and manufacturing is one of the smallest costs of the pandemic. For example the cost of a dose of Biontech Pfizer vaccine is roughly the same as the cost of getting a single antigen test performed in Germany (both roughly 20 EUR). With the variants/mutations it seems we should invest much more in vaccine capacity to avoid spending 2022 in another lockdown. > there still aren't the doses to vaccinate the planet any time in the imminent future let alone the on-the-ground infrastructure to deliver them everywhere I think the vaccinations campaigns everywhere (in the developed world at least) have shown that the infrastructure to vaccinate everyone is there if only we have enough supplies of vaccines.
      - oceanplexian 5y ago
        Half the worlds population lives on less than $5.50 per day. If you offered them 20 EUR they wouldn’t use it on a vaccine for a highly survivable disease (Compared to HIV, Malaria, and TB), they’d use it to buy food and water.
  - searealist 5y ago
    mRNA vaccines have extreme cold storage requirements that make it very difficult to distribute to many places in the world.
    - unmole 5y ago
      According to EU guidelunes, the Pfizer vaccine can be stored for a month at normal refridgerator temperature.
    - Synaesthesia 5y ago
      It's not entirely impossible, I'm sure we would be fine with in in South Africa, and many African countries. Just need consistent power. But yes that is a hindrance.
  - enaaem 5y ago
    It is not a matter of not willing to share, but a capacity problem. All production is fully bought up. Throwing more money at it won't increase the supply.
    - alsetmusic 5y ago
      > It is not a matter of not willing to share, but a capacity problem. All production is fully bought up. Throwing more money at it won't increase the supply. This is why we should suspend IP / patent protection and increase production.
      - prox 5y ago
        That has already happened I think, but creating a new pipeline is hard. https://www.theguardian.com/world/2021/may/06/covid-vaccines-what-is-patent-waiving-and-will-it-solve-the-global-shortage https://www.theguardian.com/world/2021/may/06/covid-vaccines...
      - T-A 5y ago
        Suspending IP protection does nothing to increase production capacity.
      - jlmorton 5y ago
        Moderna has said for over a year that anyone is free to use their IP. Intellectual property has precisely zero to do with production capacity.
        amluto 5y ago
        There’s IP and then there’s IP. If Moderna published their complete protocols, cell lines, etc and allowed any qualified manufacturer to pay $5k/hr to consult with Moderna experts on how exactly to manufacture the vaccine, I wonder if there would be more supply.
    - maxerickson 5y ago
      What is stopping us from linearly scaling mRNA vaccine production? If throwing money at it won't help, there should be specific answers to that question.
  - csomar 5y ago
    It's not really about being rich but availability (at least at first). The vaccine costs between $3 and $20[1] which is accessible for most of the third-world and even in most countries in Africa. > so I’m not exactly full of hope for the future right now Don't be. The vaccine is being used as a political tool currently (Pfizer good, Sinovac bad, etc...) and to restrict/grant movement around countries. 1: https://www.theguardian.com/world/2020/dec/18/belgian-minister-accidentally-tweets-eus-covid-vaccine-price-list https://www.theguardian.com/world/2020/dec/18/belgian-minist...
- chitowneats 5y ago
  The average age of death from covid is higher than the average life expectancy in the U.S. By and large Africa doesn't do mass testing the way the developed world does. No tests, no cases. Young population, very few deaths. Voila. No pandemic.
  - andai 5y ago
    Interesting perspective, I hadn't considered the age pyramid. The median age in Kenya is 20.
    - chitowneats 5y ago
      It's also not just the age pyramid. In covid deaths occurring in the under 65 population, there is often a significant comorbidity that contributed to severe illness. Obesity, diabetes, etc, are at the top of that list. Africa by and large does not have the same health profile or concerns as Japan, the UK, or the U.S. None of this is to suggest that vaccines should not be distributed there. I think they should. What I'm questioning is if COVID-19 deserves to be even on, let's say, the top 10 list of problems facing Africa in 2021. Probably not.
      - NicoJuicy 5y ago
        You're completely ignoring long covid. You don't need to die from COVID-19 to experience health issues, even without previous issues.
        chitowneats 5y ago
        Do you have any links to peer reviewed evidence of "long covid"? I haven't seen anything remotely convincing. But I am open to changing my mind.
        scotty79 5y ago
        https://www.nature.com/articles/s41591-021-01433-3 https://www.nature.com/articles/s41591-021-01433-3 https://www.healtheuropa.eu/research-shows-long-covid-is-linked-to-alteration-in-immune-system/107521/ https://www.healtheuropa.eu/research-shows-long-covid-is-lin... https://www.nature.com/articles/s41591-021-01283-z https://www.nature.com/articles/s41591-021-01283-z https://www.gov.uk/government/news/new-research-shows-2-million-people-may-have-had-long-covid https://www.gov.uk/government/news/new-research-shows-2-mill... https://www.nihr.ac.uk/news/nihr-publishes-second-themed-review-on-long-covid/27232 https://www.nihr.ac.uk/news/nihr-publishes-second-themed-rev... https://www.forbes.com/sites/ninashapiro/2021/06/20/study-documents-changes-in-brain-after-covid-19-infection/?sh=12ed9288403a https://www.forbes.com/sites/ninashapiro/2021/06/20/study-do... What exactly are you not convinced about?
- sunstone 5y ago
  The lack of cold chains in many parts of Africa will limit the places the vaccine can get to regardless of vaccine supply.
  - chitowneats 5y ago
    Excellent point.
supergirl 5y ago
I was wondering if these companies put a much higher concentration to make sure the vaccine works. it was a race to be the first mass producer of vaccine, so I imagine a discussion like "the vaccine is probably effective with a dose of X, but let's do 2*X to be sure". or in other words, if the vaccine proves not effective, at least they know it's not because of a low concentration.
- nimish 5y ago
  That's why they did the boosters too.
- handmodel 5y ago
  A huge oversight was when it was approved for phrase III they should have run many (a dozen?) different trials at different dose amounts. It was already proven to be safe and nailing the dosing would have helped get shots into arms faster in the US and elsewhere. I'm on the extreme end of thinking it should have been approved faster - but even if you are a bit of a traditionalist I don't see how running concurrent trials on such an important potential vaccine wouldn't be a huge win.
  - tgsovlerkhgsel 5y ago
    Or at least started running a second run of modified trials as soon as the phase 3 trials passed. The trials take something like 3 months from first shot to results, I think. It took a lot more than 3 months from phase 3 completed to most people vaccinated in most Western countries and obviously much longer in developing ones. But there is very little financial incentive to run such trials once you have a vaccine approved...
    - handmodel 5y ago
      100% The problem is on the government side. They should have paid for this. It would have saved them money too - if it turned out they only needed to give out one shot of the mRNA doses or that they could cut down on dosage.
  - 5y ago
msandford 5y ago
Back when this news hit (https://www.dailymail.co.uk/news/article-9033881/Half-dose-Oxford-vaccine-NOT-mistake-known-people-got-jabs-scientists-say.html https://www.dailymail.co.uk/news/article-9033881/Half-dose-O...) I suspected that we might end up finding that ever smaller amounts of vaccine would be as effective as "full" doses. Obviously I didn't make any big public predictions of such since I'm a nobody but it's interesting to see it play out.
- weaksauce 5y ago
  to expand on this... while it is encouraging to see that there is a good immune system response to such a low level of the vaccine it's also true that in the real world for pfizer the two shot course is the only way to be really protected against the Delta variant. its use in places that don't have enough doses to go around would be huge though.
  - msandford 5y ago
    Does anyone yet know why only the pfizer two shot course is effective against the delta variant yet? Slightly different spike analog, different delivery, you just need huge efficacy?
    - weaksauce 5y ago
      from reddit... > the 30µg of genetic material in the Pfizer/BioNTech vaccine vs. closer to 100µg in Moderna's indicates to me that their RNA optimization was probably superior, and is likely part of the reason for the less severe side effects https://www.reddit.com/r/medicine/comments/kp1a00/moderna_vs_pfizer/ghug7mi/ https://www.reddit.com/r/medicine/comments/kp1a00/moderna_vs... > Moderna probably used a higher dose than they needed to. This was discussed with the vaccine advisory committee. Apparently the dose they settled on for phase 3 trials was decided prior to having all the phase 2 data. They decided to error on the side of effectiveness when they picked the current dose. They basically admitted, if they knew then what they know now, they probably would have used a lower dose in phase 3. so basically 6 months ago they knew it was probably too much as to why the pfizer is effective against the delta it's probably just picking the right sequence that is slightly closer to the delta by chance.
amelius 5y ago
Is the required dose related to body weight?
- _Microft 5y ago
  I bet we could optimize the dose depending on sex, weight, age or other factors (if we knew how it depended on them) but this is not how it is done. The dose is the same for all adults.
  - acituan 5y ago
    Not really, as the trials were done on representative samples of the general population, we know at least we are not underdosing anyone wrt those metrics. Reducing the dose as much as possible would be minimizing it.
    - _Microft 5y ago
      Most likely we are just looking at this from two different points of view because in my opinion minimizing use of a resource is a form of optimization?
      - acituan 5y ago
        You're absolutely right, one could optimize with respect to any of the infinite attributes a thing has. We could have optimized for the shininess of the doses, or how good they smelled, and those would be ridiculously irrelevant properties to optimize for. The question is how relevant the use of which resources as a metric in comparison to people not getting sick? Does it even take more resources to distribute a 10x dose vaccine vs x? Is the production of the active ingredient a linear contributor to the overall cost function, which probably is dominated by a lot of the constant costs? We're not talking about 250mg vs 500mg tylenol after all.
johnchristopher 5y ago
What about Pfizer vaccine ? Are both Moderna and Pfizer close enough to speculate same results ?
- lvs 5y ago
  The Pfizer vaccine's mRNA dose is already about 1/3 of Moderna's.
- HeavenFox 5y ago
  A dose of Moderna has significantly more genetic material than a Pfizer one to begin with.
- _Microft 5y ago
  Yes, this is in the works: "A study in Belgium is comparing a lower-dose version of the vaccine from Pfizer–BioNTech against the standard dose."
Animats 5y ago
In the earliest trial of Moderna’s mRNA-based vaccine, study participants received one of three dose levels: 25, 100 or 250 micrograms. The top dose proved too toxic. The low dose elicited the weakest immune response. The middle dose seemed to offer the best balance: it triggered strong immunity and had acceptable side effects. That somewhat contradicts the article's claim. If you under-dose, there may have to be a booster shot. Then the whole inoculation program has to do the job twice.
- saddlerustle 5y ago
  100% of the population with 70% immunity results in far fewer deaths than 25% of the population with 90% immunity
  - belltaco 5y ago
    I think that calculation will vary depending on age and at risk groups. If those 25% in the second option are older folks and/or obese/diabetic, deaths might be lower in that scenario.
  - voidfunc 5y ago
    100% of the population is unrealistic tho. In the US were looking at realistically somewhere around 65-70%… stronger immunity is desirable here
    - Animats 5y ago
      We can do better than 65-70%. Here in San Mateo County, CA, 86.6% of the population over 12 has been vaccinated. Local authorities are pushing to get that higher, because there are still some cases. "Our on-the-ground experience is that we have a steady flow of positive cases – 22 new cases since yesterday, people requiring hospitalization (7 today) and supports to quarantine and isolate (6 in hotel rooms) – and that the majority of these are members of our remaining unvaccinated population ages 12+." - San Mateo County health officer. 1 death in the county this week. Moderna is adding more production lines.
- 5y ago
tbenst 5y ago
I think this makes great sense at the world population level. And after all, the Pfizer vaccine is only 30μg per dose, with equivalent (marginally higher) efficacy at preventing disease. The RNA sequences are highly similar as well, so I doubt that one expresses much more robustly. It’s been long speculated that the moderna vaccine has more side effects with same efficacy due to the aggressive dosing, and reducing to 50μg or even 25 is supported by a plethora of reasonable data.
rossdavidh 5y ago
So, I think it's great that they're looking at this, and I even believe that on balance it is probably the best bet to go ahead with this idea in countries that have a vaccine shortage. However, I just have to point out: "Levels of both antibodies and T cells were comparable to those found in people who have recovered from COVID-19." I can think of another reason this might be true. Maybe, you know, most of these people actually got covid-19, in the months after their quarter-strength vaccination. Now, this might still indicate that it helped them out, since they apparently were asymptomatic or at least did not have a serious enough case to attract the attention of the researchers, but it would not help stop the spread of the virus. So, the idea that there is no downside or risk to going with the quarter-dose, is not necessarily true. It could be that a quarter-dose leaves you just as likely to get (and perhaps spread) the virus, although it does prevent death or serious hospitalization. Again, I think on balance it's worth the risk, given the situation many countries are in, but I just think it should be acknowledged that it is still a risk.
- mrtesthah 5y ago
  > Maybe, you know, most of these people actually got covid-19, in the months after their quarter-strength vaccination. No need to speculate. This is easily disproven simply by checking for antibodies against the viral capsid and other non-RBD proteins. Those antibodies would not be present in someone unless they were actually infected.

109 points by _Microft 5y ago

This is great news for Africa which really needs vaccines right now. It's great that all this vaccine research is going on. But the inequality of access is a huge problem. Up to now Africa hasnt had a big wave of covid, but this 3rd wave has hit us really hard (and I know, Africa is not a country, I live in South Africa). What experts warned about might happen is happening now: because of insufficient vaccinations the Covid pandemic will stick around and mutate in poor countries.

deleted 5y ago
[deleted]
afavour 5y ago
This is one of the things that depresses me the most… rich countries don’t even need to be altruistic here. Be entirely selfish: send vaccines to worse off countries to cut down on the number of mutations that will inevitably arrive on your shores. The really depressing part is that the exact same logic applies to climate change, so I’m not exactly full of hope for the future right now.
- makomk 5y ago
  It doesn't matter whether your justification for why this should happen is altruism or selfishness, the same problem remains: a vaccination program of the scale and speed we've already seen is literally unprecedented, it's astounding that everyone managed this much, and yet even with that incredible effort there still aren't the doses to vaccinate the planet any time in the imminent future let alone the on-the-ground infrastructure to deliver them everywhere - and even the rich, developed countries with the best vaccine rollouts out there probably haven't reached herd immunity before new variants made that impractical or even impossible with the current vaccines. This isn't that remarkable. Previous attempts to deal with respiratory disease pandemics using vaccines have proved pretty futile, even though it is a standard part of pandemic planning.
  - oezi 5y ago
    I think the remarkable thing is that vaccine development and manufacturing is one of the smallest costs of the pandemic. For example the cost of a dose of Biontech Pfizer vaccine is roughly the same as the cost of getting a single antigen test performed in Germany (both roughly 20 EUR). With the variants/mutations it seems we should invest much more in vaccine capacity to avoid spending 2022 in another lockdown. > there still aren't the doses to vaccinate the planet any time in the imminent future let alone the on-the-ground infrastructure to deliver them everywhere I think the vaccinations campaigns everywhere (in the developed world at least) have shown that the infrastructure to vaccinate everyone is there if only we have enough supplies of vaccines.
    - oceanplexian 5y ago
      Half the worlds population lives on less than $5.50 per day. If you offered them 20 EUR they wouldn’t use it on a vaccine for a highly survivable disease (Compared to HIV, Malaria, and TB), they’d use it to buy food and water.
- searealist 5y ago
  mRNA vaccines have extreme cold storage requirements that make it very difficult to distribute to many places in the world.
  - unmole 5y ago
    According to EU guidelunes, the Pfizer vaccine can be stored for a month at normal refridgerator temperature.
  - Synaesthesia 5y ago
    It's not entirely impossible, I'm sure we would be fine with in in South Africa, and many African countries. Just need consistent power. But yes that is a hindrance.
- enaaem 5y ago
  It is not a matter of not willing to share, but a capacity problem. All production is fully bought up. Throwing more money at it won't increase the supply.
  - alsetmusic 5y ago
    > It is not a matter of not willing to share, but a capacity problem. All production is fully bought up. Throwing more money at it won't increase the supply. This is why we should suspend IP / patent protection and increase production.
    - prox 5y ago
      That has already happened I think, but creating a new pipeline is hard. https://www.theguardian.com/world/2021/may/06/covid-vaccines-what-is-patent-waiving-and-will-it-solve-the-global-shortage https://www.theguardian.com/world/2021/may/06/covid-vaccines...
    - T-A 5y ago
      Suspending IP protection does nothing to increase production capacity.
    - jlmorton 5y ago
      Moderna has said for over a year that anyone is free to use their IP. Intellectual property has precisely zero to do with production capacity.
      - amluto 5y ago
        There’s IP and then there’s IP. If Moderna published their complete protocols, cell lines, etc and allowed any qualified manufacturer to pay $5k/hr to consult with Moderna experts on how exactly to manufacture the vaccine, I wonder if there would be more supply.
  - maxerickson 5y ago
    What is stopping us from linearly scaling mRNA vaccine production? If throwing money at it won't help, there should be specific answers to that question.
- csomar 5y ago
  It's not really about being rich but availability (at least at first). The vaccine costs between $3 and $20[1] which is accessible for most of the third-world and even in most countries in Africa. > so I’m not exactly full of hope for the future right now Don't be. The vaccine is being used as a political tool currently (Pfizer good, Sinovac bad, etc...) and to restrict/grant movement around countries. 1: https://www.theguardian.com/world/2020/dec/18/belgian-minister-accidentally-tweets-eus-covid-vaccine-price-list https://www.theguardian.com/world/2020/dec/18/belgian-minist...
chitowneats 5y ago
The average age of death from covid is higher than the average life expectancy in the U.S. By and large Africa doesn't do mass testing the way the developed world does. No tests, no cases. Young population, very few deaths. Voila. No pandemic.
- andai 5y ago
  Interesting perspective, I hadn't considered the age pyramid. The median age in Kenya is 20.
  - chitowneats 5y ago
    It's also not just the age pyramid. In covid deaths occurring in the under 65 population, there is often a significant comorbidity that contributed to severe illness. Obesity, diabetes, etc, are at the top of that list. Africa by and large does not have the same health profile or concerns as Japan, the UK, or the U.S. None of this is to suggest that vaccines should not be distributed there. I think they should. What I'm questioning is if COVID-19 deserves to be even on, let's say, the top 10 list of problems facing Africa in 2021. Probably not.
    - NicoJuicy 5y ago
      You're completely ignoring long covid. You don't need to die from COVID-19 to experience health issues, even without previous issues.
      - chitowneats 5y ago
        Do you have any links to peer reviewed evidence of "long covid"? I haven't seen anything remotely convincing. But I am open to changing my mind.
        scotty79 5y ago
        https://www.nature.com/articles/s41591-021-01433-3 https://www.nature.com/articles/s41591-021-01433-3 https://www.healtheuropa.eu/research-shows-long-covid-is-linked-to-alteration-in-immune-system/107521/ https://www.healtheuropa.eu/research-shows-long-covid-is-lin... https://www.nature.com/articles/s41591-021-01283-z https://www.nature.com/articles/s41591-021-01283-z https://www.gov.uk/government/news/new-research-shows-2-million-people-may-have-had-long-covid https://www.gov.uk/government/news/new-research-shows-2-mill... https://www.nihr.ac.uk/news/nihr-publishes-second-themed-review-on-long-covid/27232 https://www.nihr.ac.uk/news/nihr-publishes-second-themed-rev... https://www.forbes.com/sites/ninashapiro/2021/06/20/study-documents-changes-in-brain-after-covid-19-infection/?sh=12ed9288403a https://www.forbes.com/sites/ninashapiro/2021/06/20/study-do... What exactly are you not convinced about?
sunstone 5y ago
The lack of cold chains in many parts of Africa will limit the places the vaccine can get to regardless of vaccine supply.
- chitowneats 5y ago
  Excellent point.

supergirl 5y ago

I was wondering if these companies put a much higher concentration to make sure the vaccine works. it was a race to be the first mass producer of vaccine, so I imagine a discussion like "the vaccine is probably effective with a dose of X, but let's do 2*X to be sure". or in other words, if the vaccine proves not effective, at least they know it's not because of a low concentration.

nimish 5y ago
That's why they did the boosters too.
handmodel 5y ago
A huge oversight was when it was approved for phrase III they should have run many (a dozen?) different trials at different dose amounts. It was already proven to be safe and nailing the dosing would have helped get shots into arms faster in the US and elsewhere. I'm on the extreme end of thinking it should have been approved faster - but even if you are a bit of a traditionalist I don't see how running concurrent trials on such an important potential vaccine wouldn't be a huge win.
- tgsovlerkhgsel 5y ago
  Or at least started running a second run of modified trials as soon as the phase 3 trials passed. The trials take something like 3 months from first shot to results, I think. It took a lot more than 3 months from phase 3 completed to most people vaccinated in most Western countries and obviously much longer in developing ones. But there is very little financial incentive to run such trials once you have a vaccine approved...
  - handmodel 5y ago
    100% The problem is on the government side. They should have paid for this. It would have saved them money too - if it turned out they only needed to give out one shot of the mRNA doses or that they could cut down on dosage.
- 5y ago

msandford 5y ago

Back when this news hit (https://www.dailymail.co.uk/news/article-9033881/Half-dose-Oxford-vaccine-NOT-mistake-known-people-got-jabs-scientists-say.html https://www.dailymail.co.uk/news/article-9033881/Half-dose-O...) I suspected that we might end up finding that ever smaller amounts of vaccine would be as effective as "full" doses. Obviously I didn't make any big public predictions of such since I'm a nobody but it's interesting to see it play out.

weaksauce 5y ago
to expand on this... while it is encouraging to see that there is a good immune system response to such a low level of the vaccine it's also true that in the real world for pfizer the two shot course is the only way to be really protected against the Delta variant. its use in places that don't have enough doses to go around would be huge though.
- msandford 5y ago
  Does anyone yet know why only the pfizer two shot course is effective against the delta variant yet? Slightly different spike analog, different delivery, you just need huge efficacy?
  - weaksauce 5y ago
    from reddit... > the 30µg of genetic material in the Pfizer/BioNTech vaccine vs. closer to 100µg in Moderna's indicates to me that their RNA optimization was probably superior, and is likely part of the reason for the less severe side effects https://www.reddit.com/r/medicine/comments/kp1a00/moderna_vs_pfizer/ghug7mi/ https://www.reddit.com/r/medicine/comments/kp1a00/moderna_vs... > Moderna probably used a higher dose than they needed to. This was discussed with the vaccine advisory committee. Apparently the dose they settled on for phase 3 trials was decided prior to having all the phase 2 data. They decided to error on the side of effectiveness when they picked the current dose. They basically admitted, if they knew then what they know now, they probably would have used a lower dose in phase 3. so basically 6 months ago they knew it was probably too much as to why the pfizer is effective against the delta it's probably just picking the right sequence that is slightly closer to the delta by chance.

amelius 5y ago

Is the required dose related to body weight?

_Microft 5y ago
I bet we could optimize the dose depending on sex, weight, age or other factors (if we knew how it depended on them) but this is not how it is done. The dose is the same for all adults.
- acituan 5y ago
  Not really, as the trials were done on representative samples of the general population, we know at least we are not underdosing anyone wrt those metrics. Reducing the dose as much as possible would be minimizing it.
  - _Microft 5y ago
    Most likely we are just looking at this from two different points of view because in my opinion minimizing use of a resource is a form of optimization?
    - acituan 5y ago
      You're absolutely right, one could optimize with respect to any of the infinite attributes a thing has. We could have optimized for the shininess of the doses, or how good they smelled, and those would be ridiculously irrelevant properties to optimize for. The question is how relevant the use of which resources as a metric in comparison to people not getting sick? Does it even take more resources to distribute a 10x dose vaccine vs x? Is the production of the active ingredient a linear contributor to the overall cost function, which probably is dominated by a lot of the constant costs? We're not talking about 250mg vs 500mg tylenol after all.

johnchristopher 5y ago

What about Pfizer vaccine ? Are both Moderna and Pfizer close enough to speculate same results ?

lvs 5y ago
The Pfizer vaccine's mRNA dose is already about 1/3 of Moderna's.
HeavenFox 5y ago
A dose of Moderna has significantly more genetic material than a Pfizer one to begin with.
_Microft 5y ago
Yes, this is in the works: "A study in Belgium is comparing a lower-dose version of the vaccine from Pfizer–BioNTech against the standard dose."

Animats 5y ago

In the earliest trial of Moderna’s mRNA-based vaccine, study participants received one of three dose levels: 25, 100 or 250 micrograms. The top dose proved too toxic. The low dose elicited the weakest immune response. The middle dose seemed to offer the best balance: it triggered strong immunity and had acceptable side effects. That somewhat contradicts the article's claim. If you under-dose, there may have to be a booster shot. Then the whole inoculation program has to do the job twice.

saddlerustle 5y ago
100% of the population with 70% immunity results in far fewer deaths than 25% of the population with 90% immunity
- belltaco 5y ago
  I think that calculation will vary depending on age and at risk groups. If those 25% in the second option are older folks and/or obese/diabetic, deaths might be lower in that scenario.
- voidfunc 5y ago
  100% of the population is unrealistic tho. In the US were looking at realistically somewhere around 65-70%… stronger immunity is desirable here
  - Animats 5y ago
    We can do better than 65-70%. Here in San Mateo County, CA, 86.6% of the population over 12 has been vaccinated. Local authorities are pushing to get that higher, because there are still some cases. "Our on-the-ground experience is that we have a steady flow of positive cases – 22 new cases since yesterday, people requiring hospitalization (7 today) and supports to quarantine and isolate (6 in hotel rooms) – and that the majority of these are members of our remaining unvaccinated population ages 12+." - San Mateo County health officer. 1 death in the county this week. Moderna is adding more production lines.
5y ago

tbenst 5y ago

I think this makes great sense at the world population level. And after all, the Pfizer vaccine is only 30μg per dose, with equivalent (marginally higher) efficacy at preventing disease. The RNA sequences are highly similar as well, so I doubt that one expresses much more robustly. It’s been long speculated that the moderna vaccine has more side effects with same efficacy due to the aggressive dosing, and reducing to 50μg or even 25 is supported by a plethora of reasonable data.

rossdavidh 5y ago

So, I think it's great that they're looking at this, and I even believe that on balance it is probably the best bet to go ahead with this idea in countries that have a vaccine shortage. However, I just have to point out: "Levels of both antibodies and T cells were comparable to those found in people who have recovered from COVID-19." I can think of another reason this might be true. Maybe, you know, most of these people actually got covid-19, in the months after their quarter-strength vaccination. Now, this might still indicate that it helped them out, since they apparently were asymptomatic or at least did not have a serious enough case to attract the attention of the researchers, but it would not help stop the spread of the virus. So, the idea that there is no downside or risk to going with the quarter-dose, is not necessarily true. It could be that a quarter-dose leaves you just as likely to get (and perhaps spread) the virus, although it does prevent death or serious hospitalization. Again, I think on balance it's worth the risk, given the situation many countries are in, but I just think it should be acknowledged that it is still a risk.

mrtesthah 5y ago
> Maybe, you know, most of these people actually got covid-19, in the months after their quarter-strength vaccination. No need to speculate. This is easily disproven simply by checking for antibodies against the viral capsid and other non-RBD proteins. Those antibodies would not be present in someone unless they were actually infected.