UPDATE: I've been digging through Pfizer's vaccine data. It's incredibly encouraging and frankly, I'm stunned that this was all done in one year.
The FDA's advisory panel will review this data publicly on Thursday. You can check it out here: 1/ fda.gov/media/144245/d…
mRNA vaccines are described as new (there aren't any on the market) but they've been studied for decades. Pfizer has overcome the challenges limiting their use, including: 1) instability of free RNA in the body, 2) unintended inflammatory outcomes, & 3) mild immune responses. 2/
It's also reassuring that Moderna had such similar topline results using the same mRNA platform. This doesn't appear to be an aberrant outcome.
If there's one thing I'd like to know more about from Pfizer's data, it's at the bottom of page 43: 3/
"In the vaccine group, one participant with baseline obesity and pre-existing atherosclerosis died 3 days after Dose 1..."
Statistically, we know bad things will happen to people whether they receive a vaccine or not. But it's not hard to imagine how some might interpret this. 4/
It will be important to achieve clarity on this, and to address a handful of cases of appendicitis in the vaccine group, to strengthen public messaging. Overall, great results!
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UPDATE: Pfizer's data demonstrates its vaccine is safe & effective (at least in the short term). But the trial wasn't designed to detect a reduction in several meaningful outcomes, including: 1) hospitalizations, 2) use of intensive care, or 3) deaths.
This isn't surprising. 1/
These trials often lack statistical power to assess severe outcomes. (Moderna won't answer the questions either). Example: we still don't know if influenza vaccination in the elderly improves mortality. Randomized trials measuring this haven't been done. thelancet.com/journals/lanin…
Pfizer acknowledged this in its data release yesterday: "higher attack rates would be needed to confirm efficacy of the vaccine against mortality." (page 48). Large observational studies will be needed, presumably after authorization.
COVID Question I've been wrestling with: How does Pfizer's vaccine actually work? There are plenty of explainers out there, but they don't give a complete picture of what's happening inside the human body. Here's what we know and what we don't: 1/
Pfizer & Moderna have created COVID vaccines using a novel platform: messenger RNA (mRNA). When one of these vaccines is injected into your arm, your cells take up the mRNA & use it to make a coronavirus spike protein.
Note: You are NOT getting injected with the full virus. 2/
Spike protein is the part of coronavirus that's responsible for binding to human cells. When your immune system sees it, a cascade of immune responses are initiated, including antibody production, that ultimately provides you with protection. 3/
COVID question: "Should people avoid Tylenol after vaccination?"
Fever is an expected side effect of mRNA vaccines & the reflex is to treat it. But treating fever can, in some cases, dampen the immune response.
When a patient gets a post-vaccination fever, what should we do? 1/
For most of the #COVID19 trials, volunteers were allowed to use temperature-lowering medications (antipyretics) after vaccination. This is understandable; fever is uncomfortable and, in rare cases, can be dangerous. 2/
But most of the time it's not. Fever is an adaptive response. It helps the immune system optimize performance. B cells make some antibodies more efficiently at higher temperatures. Treating a post-vaccination fever might be a mistake. 3/ chop.edu/news/journals-…
UPDATE: We've been clamoring to see the vaccine data for months. That will finally happen on Tuesday (December 8), when Pfizer’s info is released to the public. Here are some things I’ll be looking for that were not revealed in press releases: 1/
1. What do we know about the memory T cells of vaccinated volunteers? There’s been a shift in thinking on the role of these immune cells. They may be more important for protection than neutralizing antibodies, which have previously been the focus. 2/
2. Most major adverse events appear within 6-8 weeks of vaccination. (Minor events have a different timeline). After tens of thousands of vaccinations, there does not appear to be a common, severe side effect associated with this vaccine. What about uncommon events? 3/
COVID question I've been getting: Why do I need a vaccine when there's a 99.7% survival rate? It's a fair point (and makes for a lively discussion!).
Here is my response: 1/
Survival is an important metric, but it's the wrong one to focus on. Coronavirus is different than anything we have seen before. It causes strokes, it inflames blood vessels. It alters your sense of smell because it gets into your brain. It causes oxygen levels to plunge and.. 2/
you might not even feel it. It causes symptoms that last for months and we don't know why. When someone contracts the virus, I'm not just worried about survival. 3/
UPDATE: I’ve been asked to provide guidance to some doctors who are trying to figure out: 1) whether to take a #COVID19 vaccine issued under emergency authorization and 2) what to recommend to their patients.
Here’s my approach: 1/
On December 10, I'll watch the Vaccines and Related Biological Products Advisory Committee discuss Pfizer's data. I have many questions about subgroup efficacy, safety, & memory T cells. I’m confident those will be addressed. Then, fighting the urge to do something, I’ll wait. 2/
We’ll do it all again on December 17th when the same panel meets to discuss Moderna’s data. After that, I’ll speak with colleagues, compare notes, and hash out a recommendation. I'll explain the rationale and my level of confidence in that recommendation. 3/