Thread by @CharlesBHolmes

We now know a bit more about the safety event that led @AstraZeneca’s COVID vaccine trial to be put on hold. The trial has since resumed, but the event (and the way it was handled) has important implications for how we develop a safe, widely trusted coronavirus vaccine.

Thread

First, as many have noted, the fact that a clinical hold was placed is a sign that the regulatory process is still working, despite considerable political pressure to rush a vaccine. Clinical holds are not uncommon, even for products that ultimately prove safe & effective. (2/10)

That said, this event shows why Phase 3 trials are essential. As @adamfeuerstein from STAT news first reported, the clinical hold was placed because a participant who received the vaccine developed symptoms consistent with transverse myelitis. (3/10)

statnews.com/2020/09/09/ast…

We now know a bit more about the safety event that led @AstraZeneca’s COVID vaccine trial to be put on hold. The trial has since resumed, but the event (and the way it was handled) has important implications for how we develop a safe, widely trusted coronavirus vaccine.

Thread

Since billions of people may get this vaccine, it matters whether serious reactions are 1:10,000 or 1:10,000,000. Phase 3 trials aren't large enough to determine the exact frequency of rare reactions, but they reassure us that these events are likely to be just that – rare (5/10)

What’s also concerning is that this information was revealed not by scientists, but by AstraZeneca’s CEO on an investor call set up by JP Morgan. Safety and transparency should guide the release of information, not investment bankers’ concern for their investments. (6/10)

As @katie_thomas’s excellent NYT piece explains, greater transparency can bolster public confidence in a vaccine. This is especially important at a time when two-thirds of US voters say they won’t get a COVID vaccine as soon as it becomes available (7/10)
nytimes.com/2020/09/13/sci…

But since AstraZeneca is concerned with keeping investors happy, they shouldn’t forget that U.S. taxpayers gave $1.2 billion to develop this vaccine & agreed to buy 300 million doses. As investors & as potential vaccine recipients, the American people deserve transparency (8/10)

Public confidence in potential COVID vaccines is dropping fast. This decline is largely driven by political meddling in the regulatory process, but companies like AstraZeneca shouldn’t add fuel to the fire. (9/10)

Vaccines need to be not only safe, but trusted. Increased transparency in these trials will go a long way in ensuring that when a safe vaccine is available, people will line up to get it. Without this trust, not even the best vaccine will get us to the finish line. (10/10)

Belatedly adding in 4/10:

Transverse myelitis is an uncommon but serious neurologic disorder. It's associated with MS, viral diseases & other infections, & it has been reported rarely as a side effect from vaccines (as in, 37 total reported cases) (4/10)
pubmed.ncbi.nlm.nih.gov/19880568/