The Centers for Disease Control and Prevention signed off on a recommendation from its advisory committee Thursday that people who have a choice should get an mRNA vaccine, either Pfizer or Moderna, over the single-shot Johnson & Johnson vaccine after a review of new CDC data on rare blood clots linked to J&J.
The rare blood clots are not a new safety concern, and the J&J vaccine has already become far less common in the U.S. after it was given a Food and Drug Administration warning label about the clotting condition. But more data that confirmed a slightly higher rate of clotting cases and deaths than was previously reported caused the CDC and FDA to take another look at the data this week.
"Today's updated recommendation emphasizes CDC's commitment to provide real-time scientific information to the American public," CDC Director Dr. Rochelle Walensky said in a statement. "I continue to encourage all Americans to get vaccinated and boosted."
The CDC has now confirmed a total of at least 54 cases and nine deaths from the severe clotting event, which is called thrombosis with thrombocytopenia, or TSS, out of the 17 million people who have gotten the J&J vaccine in the U.S.
Though it's very rare, the data led CDC experts to favor mRNA vaccines by comparison, particularly because there are so many mRNA vaccines available in the U.S. and people are less likely to be limited.
There could also be more cases and deaths, because TSS is under-diagnosed and could be underreported, the CDC said.
The clotting is more common among women in their 30s and 40s but has also been seen in adult men and women of all ages.
The experts were very clear, however, that the J&J vaccine should not be taken off the shelves and is still far more beneficial than not getting any vaccine at all.
In certain parts of the U.S., particularly among prison populations, people dealing with homelessness, or rural parts of the country, the J&J vaccine is most common. And outside of the U.S., J&J has played a huge role in vaccinating populations in low-income countries -- a growing priority as it becomes clear that variants will continue to emerge until vaccination is widespread around the globe.
"In the setting where there are no alternative COVID-19 vaccines, the benefits of the J&J vaccine outweigh the risk. This is important in global situations where there may not be other COVID vaccines available," the CDC's Dr. Sara Oliver said in a presentation to the committee on the cost-benefit analysis of J&J vaccines.
With the Pfizer and Moderna vaccines, though, the protection against COVID was considered better and the side effects less severe, the CDC analysis found.
"Due to both higher vaccine effectiveness of the mRNA vaccines and the severity of safety issues seen with J&J vaccines, in the setting of widely available mRNA vaccines in the U.S., the benefit-risk balance of the mRNA vaccines is more favorable than for the Janssen vaccine," she said.
There was also discussion about the recovery from TSS, which often leads to brain bleeding and can be a harder recovery than myocarditis, the heart inflammation condition linked to the mRNA vaccines that is also a rare safety concern.
"It's important to note that there are differences in the severity of these vaccine associated events. In myocarditis after mRNA COVID-19 vaccines ... at a three-month follow up, over half reported no symptoms and over 90% were fully recovered by cardiologist or health care provider, and there have been no confirmed deaths," Oliver said.
"For TTS after the Janssen COVID vaccines, there's around a 15% mortality rate and 17% required discharge to a post-acute care rehabilitation facility," she said.
The experts on the committee were largely in agreement with the recommendation, supporting a push toward Pfizer or Moderna over J&J when available but continuing to offer J&J as opposed to no vaccination.
"I recognize the drawbacks of the Janssen vaccine. However, I look at this as an issue of the trolley problem in ethics, where you're driving the trolley and you have to decide whether you're going to go down one track and have one person die or go down a different track and have 10 people die," said Dr. Jamie Loehr, a doctor in Ithaca, New York.
"If we take away the Jansen vaccine, and people ... cannot get the mRNA vaccine, we have all these complications from getting COVID disease. And so even though there are significant risks to the vaccine, if it's the only one that is an option, I want it to be available," he said.
Dr. Beth Bell, a professor of public health at the University of Washington, said she thought the "preferential recommendation" would make it very clear that experts were concerned about the side effects but wanted to maintain individual choice.
"I would not recommend the Janssen to my family members. On the other hand, I think we do have to recognize that different people make different choices and if they are appropriately informed, I don't think we should remove that option," she said.
Some were more determined to avoid it, however.
"I just have a real problem with a recommendation for anyone to give a vaccine that 1 per 100,000 women ages 30 to 49 years old will have a condition with a case fatality rate of 15%," said Dr. Pablo Sanchez, a pediatrician at The Ohio State University Nationwide Children's Hospital.
"And so I really have a problem. I'm not recommending it to any of my patients' parents and I tell them to stay away from it," Sanchez told the committee.
For its part, J&J said it remained very confident in the positive impact of its vaccine, particularly in low-income countries.
"Let me just state at the outset that based on the data we are confident in the positive benefit-risk profile of our vaccine. It is saving lives here in the U.S. today and on every continent around the globe," Dr. Penny Heaton, global head of vaccines for J&J, said at the meeting.
"Our vaccine is different, it's long-lasting, it offers high levels of protection and it provides breadth of protection. Our vaccine has flexible dosing, it's easy to store and transport. In many low- and middle-income countries, our vaccine is the most important and sometimes the only option, even in the U.S.," Heaton said.