The FDA and CDC recommend a break in the Johnson & Johnson COVID vaccine after six women developed rare blood clots.


A halt in the use of the Johnson & Johnson COVID-19 vaccine should continue until more is known about a rare vaccine side effect, a federal advisory committee decided on Wednesday.

The committee will meet again in a week to ten days to evaluate more data that is expected to be available.

Six women in recent weeks as well as a man in a previous clinical trial developed a rare combination of blood clots and low platelet counts within two weeks of receiving the J&J vaccine. An eighth case with similar symptoms is being investigated.

The Advisory Committee on Immunization Practices for the Centers for Disease Control and Prevention met on Wednesday to discuss the cases. It can only make recommendations and does not regulate drugs, but its advice is generally regarded as a gold standard by the agencies and by other nations.

On Tuesday, the Food and Drug Administration and the CDC recommended a break in the administration of the vaccine following reports of blood clots in a small number of people who received it.

The extremely rare blood clots have been reported in seven of the 7.2 million Americans who have received the J&J vaccine. The last six cases were reported in women aged 18 to 48 years, and symptoms occurred six to 13 days after vaccination. One woman died and three remained hospitalized.

The side effect is not seen with the Moderna or Pfizer-BioNTech vaccines, which are much more available in the United States.

The J&J cases were reported to the CDC’s Vaccine Adverse Event Reporting System known as VAERS, which the CDC and FDA administer together. It acts as an early warning system to monitor the safety of vaccines.

Committee members said the system worked well and quickly identified evidence of the very rare complications within a month of the vaccine being approved.

Blood clots and COVID-19 vaccines: How researchers are beginning to address the rare side effect of the J&J and AstraZeneca vaccines

One of the reasons for the break was to warn healthcare professionals about the possibility of the rare blood clots so they can be treated properly and reported to the CDC.

There was some concern that the break could harm those who need the vaccine the most, as J&J only requires one shot and is easier to store and transport than the other two approved vaccines.

“Any extension of the break will always result in the most vulnerable individuals in the United States being the main candidates for the Janssen-Johnson & Johnson vaccine remaining vulnerable,” said Dr. Nirav Shah, director of the Maine Center for Disease Control and Prevention and director of the Association of State and Territorial Health Officials. “Those most at risk will remain at risk and those who will immediately benefit from vaccination will remain unvaccinated for an unknown period.”

Committee members noted, however, that continuing the break would not significantly affect the ability of most Americans to vaccinate. The single-dose J&J vaccine so far accounts for less than 5% of the shots administered in the United States. The other two vaccines from Moderna and Pfizer-BioNTech are more available and have not seen such side effects.

About half of J & J vaccine recipients have not yet passed the two-week mark after their shots. This means that if the side effect is more prevalent, more cases may become apparent in the next two weeks.

The experts stressed that the side effect seen was specific and extremely rare. It involved a combination of blood clots, often in the brain, with a low platelet count. Everyone who was tested also had an unusual antibody to platelets in their blood.

Experts: ‘Do not panic’ over Johnson & Johnson vaccine break. The chances of blood clots are less than 1 in a million.

The rare condition is thought to be similar to that seen in recipients of a vaccine developed by AstraZeneca and Oxford University, which is not available in the US but has been widely used in the UK and EU.

This vaccine was associated with 86 cases of blood clots plus low platelet counts in the European Union, leading to 18 deaths and 79 cases in the UK leading to 19 deaths. Most of those who developed the condition were women under 60 years of age.

The demographics in the United States have been similar to the J&J vaccine. Of the recent cases, all in adult women were under the age of 50 who received the vaccine one to two weeks before their symptoms began.

Five of the six women first reported headaches, with the sixth reporting back pain and bruising. All six developed blood clots called cerebral venous sinus thrombosis, which prevent blood from leaving the brain. Three also developed blood clots elsewhere, and four suffered cerebral blood.

A 25-year-old man who participated in the clinical J&J trial had similar symptoms of blood clots and low platelet levels and later tested positive for the same antibody. At the time, it was not clear if his condition was associated with vaccination.

The same antibody has been seen in at least 11 of the people who developed side effects after receiving the AstraZeneca-Oxford vaccine, according to a recent scientific study.

The presence of the antibody suggests that the person responds poorly to the blood-thinning heparin that at least four of the six women received before their condition was recognized. It is not clear if the woman who died was treated with heparin, according to J&J. Tests for the antibody exist but are not widely available.

Four of the women remain hospitalized while one woman and the man recovered. So far, little is known about the eighth suspect, a 28-year-old woman with similar symptoms.

Your questions answered: What do I do if I get the Johnson & Johnson COVID-19 shot?

Members of the CDC committee said Wednesday that they were not comfortable voting for the J&J vaccine until more can be learned about the condition and who is most likely to be affected.

It is possible that the committee may recommend limiting the use of the vaccine to people over 50 or 60 who appear to be unlikely to develop the condition. Several European countries have done this with the AstraZeneca-Oxford vaccine.

But it is not yet clear whether the elderly are also susceptible and just have not been identified because they are more likely to get blood clots.

Dr. Beth Bell, a committee member and public health expert at the University of Washington, said she could not vote based on so little information and as soon as the cases came to light.

“We’ve been looking at this topic for two days or less,” she said. “I just do not feel we have enough information to make an evidence-based decision.”

Dr. Sandra Freyhofer, representing the American Medical Association at the meeting, said the quick but thorough government response boosted her confidence in vaccine safety.

She told the group she supported the idea of ​​continuing a break in J&J vaccinations, “so we can find out if this is a needle in a haystack or the tip of the iceberg.”

Auto play

Show thumbnails

Show captions

Last slideNext slide

Read or share this story: