On Tuesday, CDC and FDA issued a joint statement recommending the United States pause administering Johnson & Johnson's (J&J's) single-dose Covid-19 vaccine. The agencies made the recommendation after six people who received the vaccine developed a rare and severe type of blood clot called cerebral venous sinus thrombosis (CVST).
We'll admit, the news took us by surprise—and left us with several questions on how the recommendation could affect providers on the frontlines, vaccine distribution efforts, and the nation's overall goal of achieving herd immunity. We admittedly do not have the answers to every question—and we will be watching to see what CDC's and FDA's investigations into the CVST occurrences conclude.
5 questions we're asking after the FDA recommendation
As we await further information from CDC and FDA on the CVST occurrences, we round up the five questions we're asking about the recommendation—and how they could be resolved.
1. How does the J&J vaccine pause impact supply in the United States—and can Pfizer and Moderna make up the difference?
The answer here will depend largely on time. How long will the Biden administration's J&J vaccine pause last? The United States already was expecting a significant drop in J&J supply over the next few weeks due to the manufacturing mix-up at a facility in Baltimore. So, it's really quite possible that use of J&J's vaccine (if deemed "OK" by CDC and FDA) could resume around the time manufacturing was expected to pick up again, mitigating any short-term impact on supply stemming from the pause.
If the pause is longer, the question then becomes can Pfizer and Moderna further increase capacity to make up for the planned number of J&J shots in the coming few months? The data currently suggest they can. J&J makes up less than 5% of shots in arms to date. In addition, Pfizer just announced they are increasing the number of doses they can deliver by May by 10%.
Currently, the United States is averaging 3.1 million shots per day—and some state officials have warned that they may be nearing the tipping point where vaccine supply outpaces demand. That brings us to our next question.
2. How does the news impact aggregate demand?
We already know there is a population of Americans who will not get the vaccine (Kaiser Family Foundation's Covid-19 vaccine monitor places this figure around 13%). But there's also a significant number of people (17% per KFF) in the "wait and see" group. There is reason for real concern that the J&J vaccine pause and misleading media headlines (we'll explain more below) could be seen as a reason not to get vaccinated among those who are already on the fence. If we were to see the number of people in the "no" population grow, that could have real implications for the nation's progress toward herd immunity.
Given the early data indicating J&J's vaccine may protect patients against serious disease caused by variants circulating in South Africa and Brazil, it's also possible that vaccine hesitancy linked to the J&J pause could provide more vectors for variants to spread.
3. What does reduction in supply or demand mean for variants and hospital stress?
If we do ultimately see a reduction in supply or demand, it's possible that hospitals—many of which are still recovering from the recent case surges—could again begin to see an influx of Covid-19 patients. Across the nation the number of Covid-19 hospitalizations has begun to tick up again; if this upward trajectory continues health care providers will not get their much-needed reprieve to look inward and address the emotional needs of staff who have been working around the clock amid the pandemic.
We're already beginning to see this stress in Michigan, where health care providers are battling another surge in which variants are playing a key role. Right now, Michigan appears to be a more extreme case—but many experts are watching to see if the state's experience foreshadows another broader surge.
4. What should CDC and FDA have done differently?
Given the potential ramifications, it's worth asking what CDC and FDA could have done differently. First, we want to be clear. We have no qualms with the decision to pause if there are genuine safety concerns. But communication is key. CDC and FDA in their joint statement noted they were recommending the pause "out of an abundance of caution," but they left many questions unanswered: 1) They did not give any indication of the conditions in which they might lift the pause, simply stating that the pause is recommended until they conclude their respective reviews and investigations. 2) They did not give any guidance to frontline providers in how to field questions around the vaccine from patients. 3) They did not give guidance on how states and vaccination clinics doling out J&J vaccines should adjust their processes.
Another complicating factor is how the media picked up the story. We ourselves received several breaking news alerts that the Biden administration had paused use of J&J's vaccine with little or in some cases no additional context. Media reports often failed to clarify that it is actually NOT that unusual for a newly authorized or approved treatment to see a broader array of side effects (or greater incidence) than appeared in more controlled clinical trials. That's why real-world evidence gathering is so important.
5. What should health care leaders do in the interim?
We should look for signs that FDA or CDC may re-instate J&J shots for a narrower population, potentially recommending that women 18-48 get one of the other shots. Again, this is a good thing, not a bad thing. This is why we're so lucky to have three viable vaccines in the United States, and why it's so important to have two different vaccine platforms for patients to choose from.
Continued transparent and easy-to-digest communication also will be critical in the coming days and weeks. FDA and CDC leaders need to make sure the public understands why they did what they did, how rare the side effect really is, and why—if they resume J&J for targeted groups—we should feel confident in their decision.