FDA insists Johnson & Johnson vaccine pause could be over within days but experts warn move may derail US rollout

The pause comes after six women developed a severe disorder that causes blood clots

The Food and Drug Administration (FDA) has claimed the recommended “pause” in administering the Johnson & Johnson Covid-19 vaccine could be over in a “matter of days,” as health experts warn the announcement might derail the United States’ vaccination rollout.

The federal agency alongside the Centers for Disease Control and Prevention (CDC) announced a temporary pause in administering the Covid-19 vaccine on Tuesday amid reports of six women in the US developing a severe disorder that causes blood clots. These clots formed within two weeks following vaccination.

More than 6.8 million people have received the single-dose Johnson & Johnson vaccine in the US, and about 9 million vaccine doses have been sent to states, according to data collected by the CDC.

“We are recommending a pause in the use of this vaccine out of an abundance of caution,” Dr Peter Marks, director the FDA’s Center for Biologics Evaluation and Research, and Dr Anne Schuchat, the principal deputy director of the CDC, said in a joint statement. “Right now, these adverse events appear to be extremely rare.”

All cases occurred in women between the ages of 18 to 48, and symptoms occurred six to 13 days after receiving the vaccine, according to the joint statement.

The federal agencies will now launch an investigation into these cases during the temporary pause.

“We expect it to be a matter of days for this pause,” said Dr Janet Woodcock, the acting FDA commissioner, on a phone call with reporters on Tuesday, calling it an “expeditious review”.

“We are recommending a pause in order to help the healthcare system recognise and treat patients appropriately,” Dr Schuchat added. “The safety of the vaccines and the safety of the American people is the utmost importance to us.”

This move was announced as a “recommendation” by the CDC and FDA and not a “mandate” for vaccination sites to follow.

“It’s out of an abundance of caution we’re recommending that the vaccine be paused in terms of its administration,” Dr Marks said. “However, if an individual health care provider has a conversation with an individual patient and they determine that the benefit risk for that individual patient is appropriate, we’re not going to stop that provider from administering the vaccine, because it could be right in many cases that benefit risk will be beneficial overall to that individual.” 

But it was anticipated that administering the Johnson & Johnson vaccine would be paused at all federally run sites, and already several states, including New York and Ohio, have announced they would completely pause administering the Johnson and Johnson vaccine. New York governor Andrew Cuomo told citizens to keep their appointments in the meantime, saying they would be given the Pfizer vaccine.

At this time, the federal agencies had no details on whether specific subgroups of the American population were at risk of developing blood clots after receiving the vaccine. Dr Marks said the clots likely formed due an “immune response to that occurs very, very rarely after some people receive the vaccine.”

“That immune response leads to activation of the platelets and these extremely rare blood clots,” he added.

One person who experienced a rare blood clot after receiving the Johnson & Johnson vaccine has died, Dr Marks said, and another person was in critical condition.

Members of the public who received the vaccine more than one month ago were told their risk of developing these adverse effects was “very low”. People who received the vaccine within the last three weeks were advised to monitor for any symptoms, such as severe headache, abdominal pain, leg pain or shortness of breath.

“These symptoms are different from the mild flu-like symptoms — fever and so forth — that many people experience in the couple days after receipt of the vaccine. Importantly, there are three vaccines available,” Dr Schuchat said. “And we are not seeing these clotting events with low platelet counts with the other two vaccines. People who have vaccine appointments with the other vaccines [should] continue with their appointment.”

Health experts have warned that the pause in administering Johnson & Johnson vaccines could impact the country’s vaccination rollout process, as several states scramble to rebook vaccine appointments for people who were set to receive the jab.

But Jeffrey Zients, the White House Covid-19 response coordinator, said in a statement that the pause in distribution would “not have a significant impact on” vaccinating the American public.

“Johnson & Johnson vaccine makes up less than 5 per cent of recorded shots in the arms in the United States to date,” he said. “Based on the actions of the President earlier this year, the United States has secured enough Pfizer and Moderna doses for 300 million Americans.”

Despite Johnson & Johnson making up a small percentage of available doses, the Biden administration still expected to have hundreds of thousands of doses to ship out to states each week. So the pause could cause some disruptions in the coming weeks.

The CDC will hold an emergency meeting of the Advisory Committee on Immunization Practices (ACIP) on Wednesday to review the individual blood clot cases. The FDA will also review the ACIP’s analysis as it investigates the cases.