That the US might adopt a 1 dose regimen or significantly delayed 2nd dose for vaccines already authorized seems more fanciful thought experiment than tractable policy. Pretty much all institutions and incentives are lined up against such a change and not without reason.
Current vaccines are authorized via EUAs from FDA, which both clearly state terms of use including a two-dose regimen. Moderna’s EUA says the vaccine is “administered as a series of two doses 1 month apart…”
“…Individuals who have received one dose of Moderna COVID-19 Vaccine should receive a second dose of Moderna COVID-19 Vaccine to complete the vaccination series.”…
Providers can’t just willy-nilly decide to use these vaccines another way. To do so requires changing the EUAs, which means experts at FDA & VRBPAC would have to re-review evidence to assess efficacy and safety of a different regimen.
Trials already completed for these vaccines weren’t designed to assess other regimens. Therefore, either new trials will have to be done, or regulators would use imperfect and indirect evidence to justify changes to their recommendations.
Regulators don’t seem to relish the idea of overturning the apple cart. Peter Marks at FDA has already said clearly that a one-dose approach is “foolhardy”…
He goes on to say: “from the FDA perspective we would be recommending that people complete the two-dose series so we actually that they are truly protected at the rate of approximately 95%.”
VRBPAC member Paul Offit is also skeptical. About the UK’s proposed 3-month gap between doses of the Oxford/AZ vaccine he said: “We don't have the data on the efficacy of one dose… That's why you do the studies.”…
Moncef Slaoui of Operation Warp Speed is also not a fan of changing up a regimen post-hoc. “It’s important, I think, to use the vaccine based on how you studied it” he said about the UK delayed dose approach…
CDC/ACIP would also weigh in. Currently CDC guidance says: “Limited data are currently available regarding the efficacy of a single dose. Patients should be counseled on the importance of completing the two-dose series to optimize protection.”…
Officials aren’t being obstinate, they are weighing costs and benefits based on the evidence at hand and will tend to err on the side of evidence rather than conjecture. Even getting to the current EUAs and guidance was an arduous process with a lot of tire-kicking.
Also unclear to me how executives and experts at Pfizer and Moderna would feel about their products being in ways that are different from how they had been studied. My guess is that most would not be comfortable with such a change.
Pfizer came out with a statement saying that there are "no data" to demonstrate that a single dose of its coronavirus vaccine will provide protection from infection after 21 days…
Even if new guidance were handed down from federal officials, it would still be up to states to put it into practice. We can guess that even if some states might be amendable to such changes, many might not.
Then there’s the fact that many providers might refuse to give a single dose or a significantly delayed 2nd dose. We’re already seeing significant backlash to the UK’s delayed dose proposal from providers there…
Those prioritized for vaccination early are those most at risk, such as the elderly. Postponing second shots for these individuals could place them “at the highest risk of death if they contract COVID-19” during the delay.
It will also cause logistical problems for vaccination sites. In the US, states have built current Covid vaccine delivery around the recommended two-dose regimen. It’s not a simple thing to change this up on the fly.
So, even if all the regulatory and programmatic hurdles were overcome, we’d add yet another layer of patchwork to US vaccine coverage because only some states and some providers would be implementing the new approach.
Finally, worth noting that we could have a one-dose vaccine becoming available through an EUA in the next month or two: the J&J vaccine. The US has already pre-purchased 100m doses. Fingers crossed that it's safe and effective.…
Many are rightly disillusioned with the pace of vaccine roll-out, but the most constructive use of energy may be toward the unglamorous task of improving delivery and administration of the vaccines we have through our existing (albeit imperfect) systems.

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More from @joshmich

31 Dec 20
CDC now provides more data on vaccine distribution and administration by state, agency, etc. Worth a look and a bookmark.

A few things that jumped out to me, in a short thread.…
2.17 million doses distributed through the federal pharmacy partnership prgm for long-term care, but only 167,149, or 7.8%, administered. This is the phase 1a component that needs to make up the most ground.

If this program were a state, it would easily be the worst performer.
States/jurisdictions' overall progress in administering the vaccines they have received continues to vary widely.

DC has administered over 50% of its vaccines on hand, while Kansas has administered just over 10%.
Read 6 tweets
30 Dec 20
Worth noting that Kathleen Hicks, President-elect Biden's pick for the number 2 spot at the Pentagon, would be that unusual senior defense official with some background in global health, as it relates to national security.
She's co-authored reports on the Department of Defense and global health, such as this one from 2009…
From that report: If "virulent diseases can destabilize economies and entire political systems, then it is in the national security interest of the US to address the causes of diseases and develop effective systems to detect and contain them."
Read 6 tweets
22 Dec 20
You may have seen CDC reporting 4.6 million doses of #COVID19 vaccine have been distributed & 614,117 administered. Why the huge gap between doses distributed vs administered numbers? (short thread)
Some of the gap is from reporting lag: it can take up to 3 days for providers distributing the vaccine to report to state/local health officials, and additional time for officials to report to CDC…
Also, doses distributed to states have been held for use in long-term care facilities via the federal pharmacy partnership, which is only now starting to ramp up. Its goal is to reach 4.5 million residents and staff at 55,000 nursing homes nationwide…
Read 8 tweets
4 Oct 20
I realize that without further details made public we're left picking up scraps of info about the White House cluster, but putting together a list of people and their test results and speculating about their exposures is not "contact tracing".
Contact tracing is supposed to be a methodical effort by investigators to speak with known cases, ensuring they have support and are taking proper precautions, and also ask them about their close contacts so those people can be told they have been exposed and take proper action.
Contact tracers:
-Let people know they may have been exposed and should monitor their health for signs and symptoms of the disease.
-Help people who may have been exposed get tested.
-Ask people to self-isolate if they have the disease or self-quarantine if a close contact.
Read 5 tweets
12 Sep 20
ICYMI: @KFF released the results of a new poll a few days ago, covering a number of #COVID19 topics.

I'll highlight a few of the findings in a thread.…
Among all registered voters the economy ranks as the most important voting issue, the coronavirus pandemic next. However, there is a stark difference by party, with 36% of Dems saying coronavirus is most important and just 4% of Republicans saying that. Image
If a Covid-19 vaccine became available before the election, just 4 in 10 said they would choose to get vaccinated (with Republicans slightly more likely to say no than Democrats). Image
Read 6 tweets
12 Sep 20
Contact tracing apps have evolved to become "exposure notification apps"; Apple and Google are streamlining the process of participation, allowing push notifications for users to opt-in automatically (Apple) or direct users to state-supported notification apps (Google).
The hope is that there will be much greater adoption of these apps because now opt-in will be embedded directly in device operating systems.

Adoption is state-by-state, and about 20 states have, or will soon be, deploying this approach.
Up until now, uptake of state contact tracing apps has been quite low. For example, "less than 5% of the population in North Dakota downloaded the state’s app as of June, while only about 1.8% of Utahns had done so by July."…
Read 7 tweets

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