The United States will resume use of the Johnson & Johnson Covid-19 vaccine, the Centers for Disease Control and Prevention and the Food and Drug Administration announced Friday, following an 11-day pause.
"With these actions the administration of Johnson & Johnson's Covid-19 vaccine can resume immediately," CDC director Dr. Rochelle Walensky said Friday evening during a media briefing.
The joint announcement came after a CDC advisory committee voted to recommend lifting the pause, but advised adding a warning about the increased risk of very rare but severe blood clots. The vote was 10 to 4, with one abstention for a conflict of interest.
The warnings, in the form of fact sheets that will be distributed to people who receive the vaccines, have already been prepared and approved in anticipation of the vaccinations resuming, the FDA's Dr. Peter Marks said Friday. "Those are available for use immediately."
"Today's presentations and discussions have convinced me that lifting the pause on J&J's vaccine is in the best public health interest of the U.S. population," said Dr. Henry Bernstein, a professor of pediatrics at the Zucker School of Medicine at Hofstra/Northwell in New York and a member of the CDC's advisory committee.
The CDC and the FDA recommended the pause April 13, after receiving six reports of dangerous blood clots in the brain among the more than 7 million people who had received the Johnson & Johnson vaccination.
A day later, the CDC's advisory committee, called the Advisory Committee on Immunization Practices, met to review the available data on the cases and make a recommendation on how to proceed. Ultimately, however, the committee felt it didn't have enough information to make a recommendation at that time, and instead decided to reconvene this week.
Since then, new information has emerged, including reports of an additional nine confirmed cases, for a total of 15, Dr. Tom Shimabukuro, a member of the CDC's Covid-19 Vaccine Task Force, said during the meeting Friday. A handful of other possible cases are under review, he added.
Among the confirmed cases, three patients died, and seven others remain hospitalized.
All cases were in women, and all but two were in women ages 18 to 49. Seven were among women in their 30s, occurring at a rate of 11.8 per million doses of the Johnson & Johnson vaccine administered.
Still, "the last 11 days have been reassuring that we have not identified hundreds more cases despite enhanced awareness," Dr. Grace Lee, a member of ACIP and a professor of pediatrics at the Stanford University School of Medicine, said during Friday's meeting.
No medical conditions or medications linked the cases, including obesity or use of birth control pills.
While it is true that some birth control pills carry an increased risk for blood clots, ACIP member Dr. Helen Talbot, an associate professor of medicine at Vanderbilt University in Nashville, Tennessee, pointed out the risks are very different. "My major concern about talking about this is that people are confusing the risks of this adverse event with those of oral contraceptives," adding that the types of clots are very different, as the treatments.
The CDC is calling the extremely rare combination of blood clots and low platelet counts "thrombosis with thrombocytopenia syndrome," or TTS. (Platelets are components in the blood that cause clotting; it's unusual to have blood clots and low platelets at the same time.)
Symptoms generally began at least six days following administration of the Johnson & Johnson vaccine, usually with headaches, chills, fever, nausea, weakness and stomach pain.
As the syndrome progresses, headaches tend to become much worse, sometimes combined with neck pain or stiffness. Others reported difficulty speaking or seeing clearly. Loss of consciousness and seizures were also listed as complications.
During the meeting, Dr. Joanne Waldstreicher, chief medical officer for Johnson & Johnson, shared language from a potential warning label, which reads in part that recipients of the shot "should be instructed to seek immediate medical attention if they develop shortness of breath, chest pain, leg swelling, persistent abdominal pain," as well as neurological symptoms, such as blurred vision or severe and ongoing headaches.
Of particular concern is how the condition must be treated. The standard treatment, a blood thinner called heparin, should not be used for these particular cases.
Rarely, the anticoagulant works in the opposite way, actually triggering platelets to start clotting. That mirrors the clots linked to the Johnson & Johnson vaccine. Doctors suspect heparin could worsen the condition, though none of the women who died had been given heparin.
Instead, non-heparin anticoagulants should be used, and in some cases, a therapy called intravenous immunoglobulin, Dr. Michael Streiff, medical director of the Johns Hopkins anticoagulation management service, said in a presentation during the meeting.
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He also noted that educating both health care providers and patients that this syndrome exists — and what symptoms to look out for, such as severe headache or severe abdominal pain — can help improve outcomes.
"It's clear that it in some of the cases … they tried to treat their symptoms at home for a number of days before they presented, and when they presented, they were severely ill," he said.
CDC epidemiologist Dr. Sara Oliver estimated during the meeting that by resuming the shots, there could be up to 45 cases of TTS. However, resuming use of the vaccine could reduce Covid-19 deaths by up 1,400.
"In terms of benefits, we found that for every 1 million doses of this vaccine, the J&J vaccine could prevent over 650 hospitalizations and 12 deaths among women aged 18-49, and this vaccine could prevent over 4,700 hospitalizations and nearly 600 deaths among women over 50," Walensky said.
"These are significant numbers and show the important impact of this vaccine in our country," she said. "In the end this vaccine was shown to be safe and effective for the vast majority of people."
Outside experts said they were pleased the committee recommended resuming the vaccines, even though the initial pause was "totally justified," Dr. Carlos del Rio, executive associate dean of the Emory University School of Medicine in Atlanta, wrote in an email. "When the committee first met on April 14 there were 6 cases, now there are 15. All in women."
Dr. Leana Wen, an emergency physician and former health commissioner for Baltimore, said "I think it makes sense to advise women under the age of 50 that this very rare condition could happen, and that if they are able to receive another vaccine, then they should do so."
But, Wen added, if another vaccine is unavailable, or if the recipient chooses not to get another vaccine, the Johnson & Johnson shot is "still a vaccine for which the extraordinary benefit outweighs the risks."
"For someone who is comfortable and says, 'it's a really low risk, and I'd like a shot that's one and done,' they will have that option," said Dr. Richard Besser, president of the Robert Wood Johnson Foundation and former acting director of the CDC. The Robert Wood Johnson Foundation owns stock in Johnson & Johnson, but operates independently of the company.
Besser added, "from a public health standpoint, maintaining this tool is extremely important."