Opinion: US and EU reviews of blood clots and J&J’s Covid vaccine show why a transparent process matters
When the CDC’s top advisory committee met last week to review whether a handful of very rare but potentially fatal blood clots with low platelets might be linked to J&J’s Covid-19 vaccine, the assumption was that the committee would, at the very least, follow its own agenda and vote on whether to wait for more data, or make interim age- or risk-based recommendations for the vaccine.
Instead, the committee did neither, punting its vote until this Friday when it can hold a longer discussion with the latest data. None of the ACIP members raised major concerns with the decision, or lack thereof, despite some calls to not pause the vaccine indefinitely.
But the inaction also raised concerns about whether the CDC and FDA were shirking their responsibilities and unnecessarily delaying J&J vaccinations as the race to slow the spread of the coronavirus continues.
In contrast, the European Medicines Agency’s safety committee quickly concluded its review of the blood clots and the J&J vaccine on Tuesday, deciding the vaccine’s benefits outweigh the risks, while adding a warning to the vaccine’s label, even as no one in Europe has received the vaccine yet. Following the committee’s announcement, J&J said it would resume shipments of the vaccine.
At first blush, the EMA, which just went through a similar review with AstraZeneca’s vaccine and came to a similar conclusion, seems to have been the more proactive regulator. The EMA made a quick decision on the available data and re-started the process for getting more shots into arms.
But beyond the headline and final decision lies a very different story.
In the case of the CDC’s committee, any member of the public (anywhere in the world) could turn on a computer and watch the proceedings, listen to the seriousness of the details, hear the arguments and see the slides that each of the committee members review. The public even has an opportunity to weigh in at the CDC meeting, although it’s unclear how those comments are actually used.
The ACIP decision to delay action and wait for more data on the blood clots may seem like an almost negligent response, especially given the EMA’s snap decision, when time is of the essence. But the risk calculations for the two regions are very different. The US has more of the Pfizer and Moderna Covid vaccines than the EU to fill the gap left by the J&J pause. The US also has about 10 million doses of the J&J vaccine waiting on shelves so if the FDA and CDC offer a greenlight, those doses will immediately be administered.
Also, the EMA’s safety committee completed its analysis of the J&J and AstraZeneca vaccine data behind closed doors, only offering a peek into what occurred via limited press releases and press conferences that usually lead to as many new questions as answers.
For instance, at each of the EMA press conferences on the vaccine label updates, Peter Arlett, the head of pharmacovigilance at the EMA, has unveiled new figures on the cases of blood clots with low platelets for each of the vaccines authorized in the EU.
But in doing so, Arlett fails to offer any further information on how many total doses of the vaccines have been administered or where these new cases occurred. At least twice now, either Arlett or someone else at the EMA has had to correct or clarify what the numbers mean, or where the cases did or did not occur.
If the EMA is going to release these numbers, why not put them in a press release and fully explain them? Instead, the agency leaves it to the public to decide on what they might mean, which is concerning as they are not apples-to-apples comparisons. Pfizer seeing 25 cases of the blood clots and low platelets versus J&J seeing 8 cases are not comparable considering how many tens of millions of more doses of the Pfizer vaccine have been administered.
In other instances (e.g. releasing clinical trial results), the EMA has taken a leading role in showing the world how transparency works. But in this case, even with the FDA and CDC taking extra days to make its decision, and even if the decision is to restrict the use of the J&J vaccine to a specific population, the importance of transparency is clear.