Decision comes following an EU investigation into the connection of blood-clotting and the Johnson & Johnson Covid-19 vaccine.
Johnson & Johnson says it is delaying the rollout of its coronavirus vaccine in Europe amid a US probe into rare blood clots.
The company announced the decision on Tuesday after regulators in the United States said they were recommending a “pause” in administration of the single-dose shot to investigate reports of potentially dangerous blood clots.
“We have been reviewing these cases with European health authorities,” the company said. “We have made the decision to proactively delay the rollout of our vaccine in Europe.”
Hundreds of thousands of doses of the vaccine were due to be shipped to Europe in the coming weeks.
Asked earlier on Tuesday about a possible halt to the rollout of Johnson & Johnson vaccines in Germany, a Health Ministry spokesman said there were no immediate plans to change the schedule.
“I don’t currently have the date from which Johnson & Johnson will be administered,” the spokesman, Hanno Kautz, told reporters in Berlin. “But in principle, we naturally always take such warnings in an international context seriously and investigate them.”
The European Medicines Agency, the EU’s equivalent to the FDA, said it had already started reviewing the Johnson & Johnson vaccine to assess reports of blood clots in people who received the shot.
“These reports point to a ‘safety signal,’ but it is currently not clear whether there is a causal association between vaccination” with the Johnson & Johnson shot, it said. Experts were “investigating these cases and will decide whether regulatory action may be necessary,” it added.
US health authorities took the action "out of an abundance of caution" over a disorder that appears similar to that observed in rare cases of people who received the AstraZeneca vaccine in Europe – and the shots by both companies are based on adenovirus vector technology.
All the cases involved women between the ages of 18 and 48, and symptoms occurred six to 14 days after vaccination.
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White House: Move won't impact vaccination plan
The White House on Tuesday played down the impact of a decision to pause the rollout on the wider US vaccination effort.
"This announcement will not have a significant impact on our vaccination plan: Johnson & Johnson vaccine makes up less than five percent of the recorded shots in arms in the United States to date," said Jeff Zients, President Joe Biden's Covid-19 response coordinator, in a statement.
Zients said the huge surplus in supplies of two other vaccines – Pfizer and Moderna – meant the United States could easily take up the slack after Johnson & Johnson was forced to suspend due to safety concerns.
"Over the last few weeks, we have made available more than 25 million doses of Pfizer and Moderna each week," Zients said.
"This is more than enough supply to continue the current pace of vaccinations of three million shots per day and meet the president's goal of 200 million shots by his 100th day in office."
J&J working with regulators
The CDC and FDA said the adverse events appeared to be extremely rare.
J&J said it was working closely with regulators and noted no clear causal relationship had been established between the cases and the Covid-19 vaccine made by its Janssen unit.
"I think this is a very low risk issue, even if causally linked to the vaccine: 6 cases with about 7 million doses (lower than the risk of clots with oral contraceptives) is not something to panic about," Dr. Amesh Adalja, an infectious disease expert at the Johns Hopkins Center for Health Security in Baltimore, said in an email.
"People are asking me if they should cancel their J&J vaccine appointments and I have told them not to but I know many will and this will stall progress in controlling the pandemic."
One woman died and a second in Nebraska has been hospitalised in a critical condition, the New York Times reported, citing officials.
"Even if all of the cases were caused by the vaccine, the risk of less than one in a million would have to be set against the benefits of protection from Covid-19 disease; a disease which, in itself, causes clotting in many cases," said Peter English, a retired consultant in communicable disease control and a vaccine expert.