Thread by @kakape

“I'm not here to give you the outcome of any scientific review”, says EMA director Emer Cooke at start of press conference on AstraZeneca vaccine safety. "I'm here to explain the steps in the process, what we're doing, and when you can expect us to come to a conclusion."

“This is not unexpected”, says Emer Cooke. “When you vaccinate millions of people, it's inevitable that you have rare or serious incidences of illnesses that occur after vaccination”. Role of EMA is to evaluate whether there is a causal effect or it is coincidence, she says.

Experts will meet Thursday "to come to a conclusion on the full information that has been gathered and to advise us as to whether there are any further actions that need to be taken”, says Cooke. “We will inform the public of the outcome immediately after this meeting."

“Our experts are working tirelessly to carry out this assessment as quickly as possible, but it needs a scientific evaluation”, says Cooke. “We need to have the facts first. We cannot come to a conclusion, until we've done a thorough scientific analysis."

“At present, there is no indication that vaccination has caused these conditions”, says Cooke. "They have not come up in the clinical trials, and they're not listed as known or expected side effects with this vaccine in clinical trials."

The conclusion for now? "While the investigation is ongoing, we are still firmly convinced that the benefits of the AstraZeneca vaccine in preventing #COVID19, with its associated risk of hospitalization and death outweigh the risk of the side effects”, says Cooke.

Q on batches:
Experts looking "carefully into the possibility or plausibility of any events linked to specific batches, or in fact any differences in manufacturing in any way that might lead to some disparities across batches”, says Cooke. "So that's part of the investigation."

“The decisions that are taken at a national level are being taken in the context of the information that is available at the national level” says Cooke. "It is our responsibility to focus on the science associated with these risks" and whether they are caused by the vaccines.

“The benefits continue to outweigh the risks”, says Cooke. “But this is a serious concern and it does need serious, detailed scientific evaluation."

"Our job is to make sure that we can maintain trust in these vaccines based on a proper scientific evaluation, and this is why we have put such high priority on coming to a clear conclusion based on the evaluation of the cases that are coming in as we speak”, says Cooke.

"We've been convening meetings, not just of our experts but of our heads of regulatory authorities to make sure that we have the most up-to-date information from the countries concerned”, says Cooke.

On batch issue:
“As we're seeing more events reported from across Europe, we're seeing that more batches are involved, and therefore it's unlikely that this is a batch-specific event”, says Cooke. “But we cannot rule it out."

Important:
Number of thromboses "actually far lower than we would expect in the background population”, says Peter Arlett. “Review is focusing on a small number of case reports of very rare and rather unusual thrombotic events, including thromboses combined with thrombocytopenia"

This makes epidemiological investigation harder, Arlett says, because background rates less clear, less published on it etc. “Therefore the focus becomes much more on looking at the clinical features of the individual reported case"

I asked about reports that events at least in Germany are actually cases of hemolytic uremic syndrome.
Bit of a cryptic reply: “The answer I would give at this point is that the case definition is very very important and this is what helps us to understand what we're seeing."