Feb 3, 2021 01:49 AM
(This post was last modified: Feb 3, 2021 11:30 PM by C C.)
Comparing the Covid-19 vaccines developed by Pfizer, Moderna, and Johnson & Johnson
https://www.statnews.com/2021/02/02/comp...n-johnson/
EXCERPTS: Earlier STAT published a head-to-head comparison of the vaccines developed by Pfizer and its partner, BioNTech, and by Moderna, which have been in use in the country since December. We’re updating it here with information about the J&J vaccine, with the caveat that some data from this likely new entry to the U.S. vaccination program haven’t yet been made public.
Please note that in the initial rollout of vaccine, individuals are unlikely to be offered a choice of which vaccine they want. Supplies are too scarce. The vaccine available at the place where you are being vaccinated is the one you’ll get.
[...] The Pfizer and Moderna vaccines are made using messenger RNA, or mRNA, a technology that delivers a bit of genetic code to cells — in effect, a recipe to make the surface protein (known as spike) on the SARS-2 virus. ... The J&J vaccine uses a different approach. It is what’s known as a viral vectored vaccine. A harmless adenovirus — from a large family of viruses, some of which cause common colds — has been engineered to carry the SARS-2 spike protein and to introduce the spike to the immune system, prompting it to recognize SARS-2 and protect against it.
[...] The Pfizer and Moderna vaccines have shown astonishing — and essentially equivalent — degrees of efficacy, at least in the early stages after vaccination. ... But comparing efficacy in those vaccines to the efficacy of Johnson & Johnson’s is challenging because of differences in the designs of the Phase 3 clinical tests — essentially the trials were testing for different outcomes.
[...] Because of the difference in the trials, making direct comparisons is a bit like comparing apples and oranges. ... The J&J one-dose vaccine was shown to be 66% protective against moderate to severe Covid infections overall from 28 days after injection, though there was variability based on geographic locations. ... But the vaccine was shown to be 85% protective against severe disease, with no differences across countries ... nor across age groups...
[...] It’s not yet known if any of these vaccines prevent asymptomatic infection with the SARS-CoV-2 virus. Nor is it known if vaccinated people can transmit the virus if they do become infected but don’t show symptoms.
[...] Both the Moderna and the Pfizer vaccines require two shots: a priming dose, followed by a booster shot. ... The J&J vaccine is, as mentioned, a single-dose vaccine.
[...] In the vernacular of vaccinology, vaccines that trigger a range of transient side effects in a lot of recipients are known as reactogenic. All of these vaccines — in fact, most if not all the Covid-19 vaccines that have reported data so far — fall into the reactogenic category. ... The most common side effects are injection site pain, fatigue, headache, muscle pain, and joint pain. Some people in the clinical trials have reported fever. Side effects are more common after the second dose; younger adults, who have more robust immune systems, reported more side effects than older adults.
To be clear: These side effects are a sign of an immune system kicking into gear. They do not signal that the vaccine is unsafe. [...] Figuring out how long the protection provided by any of these vaccines will last will take time... (MORE - details)
The second COVID-19 shot is a rude reawakening for immune cells
https://www.theatlantic.com/health/archi...ts/617892/
EXCERPT: Side effects are a natural part of the vaccination process, as my colleague Sarah Zhang has written. Not everyone will experience them. But the two COVID-19 vaccines cleared for emergency use in the United States, made by Pfizer/BioNTech and Moderna, already have reputations for raising the hackles of the immune system: In both companies’ clinical trials, at least a third of the volunteers ended up with symptoms such as headaches and fatigue; fevers like my husband’s were less common.
Dose No. 2 is more likely to pack a punch—in large part because the effects of the second shot build iteratively on the first. My husband, who’s a neurologist at Yale New Haven Hospital, is one of many who had a worse experience with his second shot than his first.
Recommended Reading
But much like any other learning process, in this one repetition is key. When hit with the second injection, the immune system recognizes the onslaught, and starts to take it even more seriously. The body’s encore act, uncomfortable though it might be, is evidence that the immune system is solidifying its defenses against the virus.
“By the second vaccine, it’s already amped up and ready to go,” Jasmine Marcelin, an infectious-disease physician at the University of Nebraska Medical Center, told me. Fortunately, side effects resolve quickly, whereas COVID-19 can bring on debilitating, months-long symptoms and has killed more than 2 million people.
When the immune system detects a virus, it will dispatch cells and molecules to memorize its features so it can be fought off more swiftly in the future. Vaccines impart these same lessons without involving the disease-causing pathogen itself—the immunological equivalent of training wheels or water wings.
[...] these cells dispatch molecular alarms called cytokines that recruit other immune cells to the site of injection. Marshaling these reinforcements is important, but the influx of cells and molecules makes the upper arm swollen and sore. The congregating cells spew out more cytokines still, flooding the rest of the body with signals that can seed system-wide symptoms such as fever and fatigue.
“It’s the body’s knee-jerk reaction to an infection,” or something that looks like it, Mark Slifka, a vaccine expert and an immunologist at Oregon Health and Science University, told me. “Let’s spray the area down with antiviral cytokines, which also happen to be inflammatory.” (MORE details)
https://www.statnews.com/2021/02/02/comp...n-johnson/
EXCERPTS: Earlier STAT published a head-to-head comparison of the vaccines developed by Pfizer and its partner, BioNTech, and by Moderna, which have been in use in the country since December. We’re updating it here with information about the J&J vaccine, with the caveat that some data from this likely new entry to the U.S. vaccination program haven’t yet been made public.
Please note that in the initial rollout of vaccine, individuals are unlikely to be offered a choice of which vaccine they want. Supplies are too scarce. The vaccine available at the place where you are being vaccinated is the one you’ll get.
[...] The Pfizer and Moderna vaccines are made using messenger RNA, or mRNA, a technology that delivers a bit of genetic code to cells — in effect, a recipe to make the surface protein (known as spike) on the SARS-2 virus. ... The J&J vaccine uses a different approach. It is what’s known as a viral vectored vaccine. A harmless adenovirus — from a large family of viruses, some of which cause common colds — has been engineered to carry the SARS-2 spike protein and to introduce the spike to the immune system, prompting it to recognize SARS-2 and protect against it.
[...] The Pfizer and Moderna vaccines have shown astonishing — and essentially equivalent — degrees of efficacy, at least in the early stages after vaccination. ... But comparing efficacy in those vaccines to the efficacy of Johnson & Johnson’s is challenging because of differences in the designs of the Phase 3 clinical tests — essentially the trials were testing for different outcomes.
[...] Because of the difference in the trials, making direct comparisons is a bit like comparing apples and oranges. ... The J&J one-dose vaccine was shown to be 66% protective against moderate to severe Covid infections overall from 28 days after injection, though there was variability based on geographic locations. ... But the vaccine was shown to be 85% protective against severe disease, with no differences across countries ... nor across age groups...
[...] It’s not yet known if any of these vaccines prevent asymptomatic infection with the SARS-CoV-2 virus. Nor is it known if vaccinated people can transmit the virus if they do become infected but don’t show symptoms.
[...] Both the Moderna and the Pfizer vaccines require two shots: a priming dose, followed by a booster shot. ... The J&J vaccine is, as mentioned, a single-dose vaccine.
[...] In the vernacular of vaccinology, vaccines that trigger a range of transient side effects in a lot of recipients are known as reactogenic. All of these vaccines — in fact, most if not all the Covid-19 vaccines that have reported data so far — fall into the reactogenic category. ... The most common side effects are injection site pain, fatigue, headache, muscle pain, and joint pain. Some people in the clinical trials have reported fever. Side effects are more common after the second dose; younger adults, who have more robust immune systems, reported more side effects than older adults.
To be clear: These side effects are a sign of an immune system kicking into gear. They do not signal that the vaccine is unsafe. [...] Figuring out how long the protection provided by any of these vaccines will last will take time... (MORE - details)
The second COVID-19 shot is a rude reawakening for immune cells
https://www.theatlantic.com/health/archi...ts/617892/
EXCERPT: Side effects are a natural part of the vaccination process, as my colleague Sarah Zhang has written. Not everyone will experience them. But the two COVID-19 vaccines cleared for emergency use in the United States, made by Pfizer/BioNTech and Moderna, already have reputations for raising the hackles of the immune system: In both companies’ clinical trials, at least a third of the volunteers ended up with symptoms such as headaches and fatigue; fevers like my husband’s were less common.
Dose No. 2 is more likely to pack a punch—in large part because the effects of the second shot build iteratively on the first. My husband, who’s a neurologist at Yale New Haven Hospital, is one of many who had a worse experience with his second shot than his first.
Recommended Reading
But much like any other learning process, in this one repetition is key. When hit with the second injection, the immune system recognizes the onslaught, and starts to take it even more seriously. The body’s encore act, uncomfortable though it might be, is evidence that the immune system is solidifying its defenses against the virus.
“By the second vaccine, it’s already amped up and ready to go,” Jasmine Marcelin, an infectious-disease physician at the University of Nebraska Medical Center, told me. Fortunately, side effects resolve quickly, whereas COVID-19 can bring on debilitating, months-long symptoms and has killed more than 2 million people.
When the immune system detects a virus, it will dispatch cells and molecules to memorize its features so it can be fought off more swiftly in the future. Vaccines impart these same lessons without involving the disease-causing pathogen itself—the immunological equivalent of training wheels or water wings.
[...] these cells dispatch molecular alarms called cytokines that recruit other immune cells to the site of injection. Marshaling these reinforcements is important, but the influx of cells and molecules makes the upper arm swollen and sore. The congregating cells spew out more cytokines still, flooding the rest of the body with signals that can seed system-wide symptoms such as fever and fatigue.
“It’s the body’s knee-jerk reaction to an infection,” or something that looks like it, Mark Slifka, a vaccine expert and an immunologist at Oregon Health and Science University, told me. “Let’s spray the area down with antiviral cytokines, which also happen to be inflammatory.” (MORE details)