Johnson & Johnson says it is pausing clinical trials for its single-dose COVID-19 vaccine and delaying the shot’s rollout in Europe as reports of blood clots in at least six recipients cause concern in the United States and Canada.
The U.S. Food and Drug Administration and the U.S. Centers for Disease Control and Prevention said in a joint statement Tuesday that it was recommending an immediate “pause” in the shot’s use “out of an abundance of caution.”
“I’d like to stress: these events appear to be extremely rare,” Janet Woodcock, the acting commissioner of the FDA, said at a virtual news conference Tuesday.
“However, COVID-19 vaccine safety is a top priority for the federal government and we take all reports of adverse events following vaccination very seriously.”
Later Tuesday, Johnson & Johnson said in a statement that it will be pausing vaccinations in all clinical trials run by the company’s pharmaceutical arm, Janssen, “while we update guidance for investigators and participants.”
The company also said it will “proactively delay” the shot’s rollout in Europe due to the reports. The J&J vaccine has been approved for use by the European Union but a rollout had yet to begin before the U.S. reports emerged.
The calls for a pause stems from six U.S. reports of extremely rare clotting called cerebral venous sinus thrombosis (CVST), which has been seen in combination with low levels of blood platelets, called thrombocytopenia.
All the six recipients were women between the ages of 18 and 48. One woman died and a second woman has been hospitalized in critical condition, officials said.
The Virginia Department of Health later confirmed the fatal case occurred in that state in March.
The U.S. experts acknowledged how rare the events are in the grand scheme of things — with more than 6.8 million doses of the J&J vaccine having been administered in the country so far — but said their recommendation relates more to the treatment of CVST.
Top U.S. infectious diseases official Dr. Anthony Fauci said there was no reason for anyone to be anxious if they had already received the J&J vaccine.
“Someone who maybe had it a month or two ago would say, ‘what does this mean for me?’ It really doesn’t mean anything,” he said.
“You’re okay, because if you look at the frame, the time frame, when this occurs, it’s pretty tight from a few days, six to 13 days from the time of the vaccination.”
Dr. Anne Schuchat, principal deputy director of the CDC, said pausing the use of the vaccine will help the healthcare system prepare “to recognize and treat patients appropriately and to report severe events that may be seen in people who have received the J&J vaccine.”
The issue is that the “standard treatment doctors have learned to give for blood clots” shouldn’t apply in these situations, said Dr. Peter Marks, director of the FDA’s Center for Biologics Evaluation and Research.
In fact, that standard treatments could cause “tremendous harm, or the outcome could be fatal” for vaccine recipients, he said, so “alternative treatments need to be given.”
“We need to make sure providers are aware that if they see people who have low blood platelets, or if they see people who have blood clots, they inquire about history of recent vaccination and then act accordingly.”
The CDC will convene a meeting of the Advisory Committee on Immunization Practices (ACIP) on Wednesday to further review these cases and assess their potential significance. The FDA will then review that analysis as it also investigates these cases, it said in a statement.
Though Marks said “this is a recommendation, not a mandate,” it’s expected U.S. federal distribution channels, including mass vaccination sites, will pause the use of the J&J shot. States and other providers are expected to follow.
A timeframe for the pause is unclear, though the experts say it should be only a matter of days before a review and “aggressive outreach to clinicians” is completed.
In the meantime, recipients of the vaccine who experience severe headache, abdominal pain, leg pain, or shortness of breath within three weeks of receiving the shot are being asked to contact their health care provider.
“Our partners will be working to reschedule people who have the J&J vaccine appointments in the days ahead,” said Schuchat. “This may be a bit bumpy, we want to make sure we’re getting the word out to the public and our providers.”
The move from the U.S. regulators comes less than a week after Europe’s drug regulator said it was reviewing rare blood clots in four people in the U.S. who received the shot.
The reports appear similar to a rare, unusual type of blood clotting disorder that the European Medicines Agency says is possibly linked to Oxford-AstraZeneca’s COVID-19 vaccine. The EMA’s review prompted many European countries to change their recommendations for AstraZeneca.
The AstraZeneca shot has not yet been cleared in the U.S. but has been approved for use in Canada since February.
Canada also moved to change recommendations for use of the AstraZeneca vaccine after the reports of very rare blood clots in some recipients, although there had been no such reports in the country until Tuesday when the public health agency announced its first patient.
Canada approved the one-shot Johnson and Johnson vaccine in early March.
On Tuesday, Health Canada said it is “following the issue closely” and working with the drugmaker, the U.S. FDA and other regulators as the data related to the very rare blood clots are reviewed.
The agency has also asked Janssen to provide information on any cases so it can conduct its own analysis.
Canada’s first deliveries of the shot are not expected to begin until the end of April. Prime Minister Justin Trudeau said Tuesday that those shipments are “still on track.”
Canada has pre-ordered 10 million doses of the Johnson & Johnson vaccine, with options to order up to 28 million more.
A spokesperson for Janssen Canada previously told Global News on March 31 that it anticipates fulfilling the 10 million doses by the end of the third quarter “with first delivery targeted in the next several weeks.”
Reaction to J&J’s pause in the U.S. was swift.
Dr. William Schaffner, an infectious disease doctor at Vanderbilt University Medical Center in Nashville, told Reuters that the pause “shows our vaccine surveillance system is really working.”
“It certainly is concerning because the other vaccine in which this issue has been raised is also the other adenoviral vector vaccine, so you have to worry about that,” he said.
“That I think contributed to the very quick action of the CDC that is going to put the use of this vaccine on pause.”
The Dutch medicines regulator said the benefits of the vaccine outweigh the possible risks. Spain’s prime minister took a similar stance.
Australian authorities, however, said Tuesday it has no current plans to add the one-dose vaccine to its immunization plans, as it moves away from procuring vaccines under review over blood clots.
The World Health Organization said it awaits reviews from the U.S. and European regulators.
— with files from Global News’ Emerald Bensadoun and Sean Boynton, Reuters and the Associated Press