New data from Novavax vaccine just showed that UK & esp South African variants are more problematic in real world than lab experiments suggested. Implications are profound for 2021 and beyond.…
Vaccine worked well to stop original strain (96%), like mRNA vaccines, but less effective for new strains (86% for UK strain, 60% protective against South African strain). My guess is that if mRNA vaccines were tested now in a clinical trial in South Africa...
...they would show similar reduction in effectiveness. Bottom line, new SA strain has evolved SOME (not total) resistance to current vaccines. Current vaccines still help blunt severity, so worth getting even in South Africa.
But this means that even if everyone got the current vaccine and stopped social distancing, then new variant could end up causing more harm than SARS2 does now. That’s the big deal. New variant is extending the pandemic until we have new vaccines.
Everyone who got first vaccine will want a booster shot against the new SA variant. Ultimately, we need combo vaccines that immunize against both original and SA strains.
Novavax is responding logically, by advancing a combo vaccine into clinic that will include South African spike antigen that they say will enter trials in 2Q21. I assume it takes 3 months more for early evidence of effectiveness against SA strain, so summer maybe.
mRNA companies are also working on vaccine against new strain. They will probably be able to roll out boosters soonest of any companies for people who already got vaccines & just need new booster. But will be interesting to see how they develop a combo vaccine for first timers.
That’s because mRNA vaccines are limited by tolerability in how much mRNA you can jam into a dose. The more mRNA you give, the more painful, more fever, etc. It’s easier to double and triple up the antigens for a more conventional protein-based vaccine.
That’s b/c protein vaccine uses a separate immune stimulating adjuvant. Can give 2, 3, 4 proteins covering unique strains while keeping dose of adjuvant the same, so immune system isn’t over-stimulated. But mRNA is its own adjuvant; so more strains means more immune stimulation.
What about JNJ & AZ adenoviral vaccines? We’ll likely see next week how effective JNJ’s is against original & new strains but odds are it will be less effective against new strain. Since Ad vaccines probably can’t be redosed (immune system learns to recognize & reject vector)...
...those vaccines won’t be good for keeping up with new strains. So I don’t see adenoviral vaccines as useful for the long run management of SARS2 due to weak efficacy and challenge with redosing.
If SA variant is last variant we need to defeat (unlikely), we’ll be able to do so w/ mRNA & protein vaccines. But if new variants keep emerging, we may need to expand vaccines to more antigens than mRNA seems to tolerably accommodate, putting all focus on protein-based vaccines.
So sadly I now think 2021 is going to be rough & we’ll be talking about progress of vaccines against new strains. If we see data by MY21 that new vaccines against new strain work, then hopefully FDA allows faster approval of subsequent upgrades in response to yet new strains.
Key is to keep investing in expansion of manufacturing capacities of the vaccines that are most likely to allow us to expand them to cover more strains and to redose with boosters. That means investing in massive scale-up of protein-based vaccines.
And it also means that we’ll need to continue conducting global surveillance for emergence of new variants to give vaccine companies a head start to update their vaccines. That means more sequencing of positives samples, particularly in regions with escalating infections.
These data are painful for what they mean for the world. This virus is a tough opponent. Just shows how critical vaccines, therapeutics, & diagnostics remain to fighting this virus. It’s going to be with us forever, not just killing but causing all kinds of disabilities.
We’ll be updating our map and doing some more analysis. I’m sure our team will be having an active debate on our next RA TV episode. check out
Update: like AZ’s, JNJ vaccine less effective on original strain than other vaccines (insight into Ad vector) &, as w/Novavax, less effective against new SA strain (insight into virus). Worth taking b/c blunts severity of disease regardless of strain.…
So we have to 1) roll out existing vaccines asap, 2) people should take them, 3) remain cautious (esp around unvaccinated) b/c SA strain can spread despite vaccine & mod disease isn’t fun, & 4) upgrade vaccines to cover SA strain, for which adjuvanted vaccines are well suited.

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More from @PeterKolchinsky

17 Jan
This new variant is making a lot of people REALLY nervous. Here’s why it should & shouldn’t. I’ll hit on infectivity, lethality, vaccine effectiveness, & some “what ifs”. Yes, it’s more infectious. That means that w/ comparable carelessness... 1/17 variant will infect more people. Once a person is infected... new variant is not more lethal (though like original strain, it’s bad enough). While not more lethal at level of individual person once they are infected, it’s more lethal at societal level b/c more infectious.
Lethality aside for a moment, not enough attention has been given to what this virus does short of killing. For example, it can rob you of sense of smell, which means taste, for weeks or months. Sound mild until you experience it- it’s a pretty miserable condition. 3/17
Read 18 tweets
24 Dec 20
Does being vaccinated mean you don’t have to wear a mask? Answer: no, mask up, please. B/c vaccine protects you from getting sick if you are exposed to virus, but it doesn’t reliably stop virus from hitching a ride in your nose & jumping to someone else. 1/6
We know the vaccines don’t entirely stop people from getting sick if exposed. They reduce risk by 95% (20-fold). But as people start mingling much more after vaccination, they increase their odds of exposure. 2/6
So think of it this way. Social distancing and masks reduce your risk of being exposed to the virus. And a vaccine reduces your risk of getting sick if you are exposed. But if you stop social distancing, you are way more likely to get exposed. 3/6
Read 6 tweets
25 Oct 20
What would you change US stock market hours to if you could & why? (long on thoughtfulness please, funny is an option, keep puns short)
Here’s another thought. How about introducing newly public companies to market by starting with short trading hours, 3 days a week & then opening up to standard hours after 1-2 years?
What would be ideal public exchange hours from the standpoint of emerging biotech companies (consider their needs) and the funds that provide most of their backing?
Read 5 tweets
24 Oct 20
Once covid vaccines launch, we might trick ourselves into believing they cause everything from colorectal cancer to diabetes to heart disease & lupus. Well-meaning data miners could do real harm. We need to vaccinate ourselves against that. Here’s how. 1/
Consider that many people have avoided going to the doctor for regular checkups during covid. They haven’t gotten preventative care. They haven’t been diagnosed with emergent conditions. They might now have heart disease or cancer and not yet know it. 2/
Here’s a paper showing that cancer diagnoses have gone down during covid. They say “The delay in diagnosis will likely lead to presentation at more advanced stages and poorer clinical outcomes.“… 3/
Read 20 tweets
16 Oct 20
Delays in FDA approval of a vaccine probably won’t change when most of us get a vaccine. PFE says it might be able to seek approval by end of Nov, so Dec approval possible. But will only have 100M doses ready by YE (50M courses). So unless you have...…
So unless you have reason to think you would be among the 50M first up to get vaccinated, what will determine when you get vaccinated is the pace of production. & for most of us, our ticket likely won’t be called until 2Q21. So approval delays of 1-2 months won’t change that.
You might even prefer that the vaccines be vetted more carefully. Of course, the people who would be impacted by delays are those slated to get the first doses. Front-line workers, vulnerable. They too might prefer to know the vaccines are safe and effective.
Read 6 tweets
29 Sep 20
It seems @icer_review’s heart is showing a little in today’s report on essential compassion & fairness of proper insurance w/ low OOP costs for medicines. But they still have a lingering attachment to math that’s been rightly criticized as racist...… 1/ patient advocate @SuePeschin in this short, incisive piece.… I wonder if it’s a bit uncomfortable for policymakers ICER claims to have influenced w/ its math. After all, #badmathkills 2/
.@icer_review says if medicines for kids w/ sickle cell disease don’t make the cut according to their math (which @SuePeschin has pointed out is deeply flawed), insurance should make those meds unaffordable to them (w/ high OOP costs) as leverage over drug companies. Harsh.
Read 9 tweets

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