Top US health officials on Tuesday called for a pause in the use of the Johnson & Johnson COVID-19 vaccine as they review cases of rare blood clots in people who received the injections.
The officials said they are investigating six cases of a “rare and serious type of blood clot” in more than 6.8 million people in the US who have received the Johnson & Johnson vaccine.
All six cases were in women between the ages of 18 and 48.
The Centers for Disease Control and Prevention (CDC) Advisory Committee on Immunization Practices will meet on Wednesday to review the cases, and the Food and Drug Administration (FDA) will also investigate them.
“Until that process is complete, out of an abundance of caution, we recommend a break in the use of this vaccine,” said Peter Marks, a top FDA official, and Anne Schuchat, a top CDC official, in a joint statement. “This is important in part to ensure that the healthcare provider community is aware of the potential for these side effects and can plan for appropriate recognition and treatment because of the unique treatment required with this type of blood clot.”
The type of blood clot in question, called cerebral sinus venous thrombosis, requires different treatment than blood clots usually do. The agencies said they want healthcare providers to be able to plan for them.
Marks and Schuchat stressed that “these side effects appear to be extremely rare.”
“The safety of the COVID-19 vaccine is a top priority for the federal government and we take all reports of health problems following vaccination with COVID-19 very seriously,” the official added. “People who have received the J&J vaccine who develop a severe headache, abdominal pain, leg pain, or shortness of breath within three weeks of vaccination should contact their healthcare provider.”
The move will certainly cause shock waves from the US vaccination efforts and could exacerbate reluctance to aggravate vaccinations, which has already been a problem as some people refused to be vaccinated.
Still, two other vaccines, from Pfizer and Moderna, have made up most of the U.S. supply so far, and no serious safety concerns have been raised with them.
To date, approximately 7 million Johnson & Johnson injections have been administered in the US, compared to much higher figures for Pfizer and Moderna, approximately 98 million and 85 million, respectively.
Health officials stressed during a phone call with reporters that the blood clots are “extremely rare,” but said it takes time to warn health care providers about treating patients who do have the problem. The standard treatment for blood clots, a drug called heparin, can cause “tremendous damage” in patients who receive the vaccine, so doctors should know to use alternative treatments, Marks said.
“The time frame will obviously depend on what we learn in the coming days, but we expect it to be a matter of days before this pause,” said Acting FDA Commissioner Janet Woodcock.
When asked if the pause was an overreaction given how rare the blood clots appear to be, officials pointed to a balance between alerting health care providers and the severity of the pandemic.
“When we saw this pattern and knew that treatment needed to be individualized for this condition, it was of the utmost importance for us to get it known,” said Schuchat. “That said, the pandemic is quite serious and cases are increasing in many places and vaccination is critical, so we want to make sure we make some recommendations quickly.”
Officials said there have been no reports of this blood clotting problem in people who received the Pfizer and Moderna vaccines.
Johnson & Johnson also struggled to produce it, with problems at a Baltimore facility slowing down the distribution of more doses. But there are still about 9 million Johnson & Johnson recordings that have been distributed, according to data from the CDC, which are now on a hiatus.
“While it is unfortunate, it is the right step,” said Ashish Jha, Dean of the Brown School of Public Health, wrote from the break on Twitter. “Central to the success of vaccinations is ensuring that people can trust them to be safe. These events (central venous thrombosis) are VERY rare. 6 out of 7 million. No vaccine (or drug) is perfect. But trust is based on a system that takes adverse events seriously, she investigates, makes data-driven decisions. ”
The move brings to the US some of the back and forth that has been happening in Europe about another vaccine, from AstraZeneca, which has also been interrupted in some countries due to rare blood clots. That vaccine has not yet been approved by the FDA for use in the US.
Updated at 11am