US Regulator Adds Bleeding Risk to J&J COVID-19 Vaccine Fact Sheets

A vial of Johnson & Johnson's COVID-19 vaccine sits at a vaccination clinic in Los Angeles, Calif., on Dec. 15, 2021. (Frederic J. Brown/AFP via Getty Images)

Food and Drug Administration officials on Tuesday added a bleeding risk to fact sheets for Johnson & Johnson’s COVID-19 vaccine.

Healthcare providers administering the vaccine and recipients and caregivers are now being told that there’s a safety signal for immune thrombocytopenia, a disorder stemming from low platelet levels that can cause excessive bleeding.

“Reports of adverse events following use of the Janssen COVID-19 Vaccine under emergency use authorization suggest an increased risk of immune thrombocytopenia (ITP) during the 42 days following vaccination,” the regulator tells administrators (pdf).

“The chance of having this occur is very low,” it said in the sheet (pdf) for recipients and caregivers.

People who have been diagnosed with ITP before should discuss with their healthcare provider the risk of the condition from vaccination and a potential need to monitor platelets if they move forward with getting the vaccine.

Janssen is a subsidiary of Johnson & Johnson (J&J). The company did not respond to a request for comment on the updates.

The Vaccine Adverse Event Reporting System, to which people file reports of post-vaccination adverse events, was not working on Wednesday.

When ITP occurs, blood doesn’t clot as it should, according to the National Institutes of Health. The condition is due to a low number of platelets or thrombocytes. People with the condition may experience bleeding; signs of the condition include red or purple dots on the skin, nosebleeds, and heavy menstrual bleeding.

The European Medicines Agency, Europe’s drug regulator, added information about ITP risk following J&J’s vaccine last year.

Administrators and recipients of the J&J vaccine in the United States were already warned that some people who have received the shot have been diagnosed with thrombosis with thrombocytopenia syndrome, or low blood platelet levels combined with blood clotting.

Though the condition has rarely been reported following receipt of the vaccine, U.S. health authorities said last month the other COVID-19 vaccines authorized or approved in the country are “preferred” because of concern over the syndrome.

Only three vaccines have been cleared by U.S. regulators. The other two, one from Moderna and one from Pfizer and BioNTech, were created using messenger RNA technology. The J&J vaccine utilizes an adenovirus vector.

Still, people who are “unable or unwilling” to get the Moderna and Pfizer jabs should still get vaccinated with the J&J one, Centers for Disease Control and Prevention Director Dr. Rochelle Walensky has said.

As of Tuesday, just 17.8 million doses of the J&J shot have been administered in the United States, versus nearly 200 million Moderna shots and over 300 million Pfizer jabs.