Digging into the detailed EMA report on the AZ vaccine investigation. (The committee vote for their decision was 31 out of 32.) They discuss several hypotheses that have been proposed for the phenomenon, if it's triggered by the vaccine.
..1st was one from researchers in Germany/Austria, based on studying several of the people: that it's similar to heparin-induced thrombocytopenia ("HITT-like"), & related to Platelet Factor 4. assets.researchsquare.com/files/rs-36235… (preprint)...2/n
...EMA conclusion: there are similarities, so still needs to be investigated. But there are differences too: eg HITT doesn't cause a condition that occurred here (DIC). So they called this unproven...3/n
...Next one: could it be unrecognized Covid-19, as coagulation problems are a feature of the disease? Their conclusion: still to be investigated, but too many people tested negative for the disease - & it wouldn't explain why it was happening with 1 vax & not the others...
..Another. Could it be because the AZ vax codes not just for the virus' protein, incl a tPA to increase immunogenicity? But they knew of no evidence it could, eg, interfere with platelets. They don't expect the issue is not using the same protein sequence other vaxes use ...5/n
...Another hypothesis: could it be the SARS-CoV-2 spike protein immunogen encoded in the AZ vaccine? They considered this unlikely, because it wouldn't explain why it wasn't occurring as often with other vaccines that use very similar immunogens...6/n
...Another: could it be impurities or other components of the vaccine? They didn't think this could explain it. If it was impurities, it would have been related to specific batches & it isn't. They don't suspect any of the other components ...7/n
...Could it be caused by the chimpanzee adenovirus vector? One of the EU countries thinks it's likely, but though the committee agreed it's plausible, they think it's more likely the cause is some kind of link with Covid-19 specifically, not the adenovirus...8/n
...So. No answer here. Just a mystery that needs to be solved. And a very long to do list for investigators. /9
...aaaand PS: Several tweets asking, do they think it's because the AZ vaccine doesn't use the 2P protein that the mRNA vaxes, J&J, & Novavax use? That's in the 5th tweet in this thread: this group didn't suspect that's why. Here's that conclusion. 10/10
...2nd PS: I hadn't read the report before - turns out it's not a new one from today. (Thanks, @irishinneburg!) The hypotheses gel with what they said at the press conference though.

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More from @hildabast

7 Apr
EMA is listing unusual blood clots with low platelets as a side effect of the AstraZeneca Covid vaccine ema.europa.eu/en/news/astraz… 1/n
...90 cases: 62 with CVST & 24 with splanchnic vein thrombosis (that's abdominal). 18 of 90 people died. It was 90 out 25m, so less than 4 per million. An immune response is a plausible explanation for this, they conclude. 2/n
...MHRA's press conference is delayed, so no word yet there... 3/n
Read 23 tweets
22 Mar
Oh this is great news! 🥳

Oxford-AstraZeneca vaccine: 79% efficacy & possibly increasing over time

Press release for interim efficacy results from the US trial for 32,449 people, randomized 2:1 to placebo (140 events - symptomatic Covid-19)... 1/n

... Typo in previous tweet: 141 events. (No confidence intervals provided.)

...Vaccine efficacy was consistent across ethnicity & age, include older. It was 80% for people aged 65 & older.

No breakdown of events by vaccine & placebo...3/n
Read 8 tweets
22 Mar
Distracted by the other EMA thing, I'm only just catching up with the 218-page EMA assessment report for the J&J vaccine ema.europa.eu/en/documents/a…

For background, my summary from the 62-page FDA report is here absolutelymaybe.plos.org/2021/03/16/com…

Tweeting about what's new or different...1/n
...As usual, in-depth look at quality of manufacturing. "No raw materials of human or animal origin are used" in the final production. The cell line used to optimise production of the vaccine vector is PER.C6, which has already been studied for safety...2/n
...Current batches manufactured mostly in Leiden & emerging in Baltimore: they've shown consistency in the European manufacture - EMA wants them to follow-up with data showing the Baltimore production is comparable (this is all standard) ...3/n
Read 19 tweets
21 Mar
Out of the several different major vaccination strategies internationally, the UAE's is one of the most unusual. There are 4 vaxes available (Sinopharm Beijing, BNT-Pfizer, Sputnik V, Oxford-AstraZeneca), & free vaccination now open to everyone 16+ khaleejtimes.com/coronavirus-pa… ...1/n
... When you apply for an appointment, you choose the vaccine you want.... "Press 1 for Sinopharm...."

(Here from when there were 3 vaccines) khaleejtimes.com/coronavirus-pa… ...2/3
...Over 56% of the population has had at least 1 dose; over 72% of seniors & people with chronic diseases. As of now, open to everyone.


JHU's tracker says 23% of the population is fully vaccinated coronavirus.jhu.edu/vaccines/inter… 3/3
Read 4 tweets
11 Mar
The Danish Health Authority has suspended use of the Oxford-AstraZeneca Covid vaccine for 14 days as a precaution while an investigation into serious adverse events proceeds...1/n sst.dk/da/Nyheder/202… HT @iamPWK
...There is no confirmation that the vaccine caused any of the serious adverse events (SAEs) under investigation: this is a precaution, while the investigation proceeds. The SAEs are related to blood clots in Austria & Denmark ...2/n
...There were 2 thrombosis-related (blood clot) SAEs in Austria & the first investigation was whether it was related to a specific batch of vaccine. The EMA (Euro drug regulator) determined that there wasn't a problem with the batch...3/n
Read 5 tweets
10 Mar
Data & Safety Monitoring Board for phase 3 trial of Sinopharm's vaccines in Peru - about 12,000 people, 2 vaccines vs placebo - has recommended discontinuation of the Wuhan vaccine arm for inadequate efficacy (*not* the Beijing vax in use globally) ...1/n cayetano.edu.pe/cayetano/es/no…
...The university running the trial have sought the permission of the drug regulator to unblind participants & offer the volunteers in the Wuhan & placebo arms vaccination with the Beijing vaccine which did meet efficacy criteria (results aren't ready for release though)...2/n
...Sinopharm recently issued a press release saying the Wuhan vaccine efficacy rate was 75%. They applied to NMPA (China's drug regulator for authorization). NMPA authorized it on Feb 27 ...3/4 english.nmpa.gov.cn/2021-02/27/c_5…
Read 4 tweets

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