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FDA, CDC Pauses J&J COVID-19 Vaccine Due To Rare Blood Clot Cases
Six cases of a rare and dangerous blood clot have been reported among women ages 18 to 48 who received the Johnson & Johnson COVID-19 vaccine.
The CDC and FDA are reviewing data involving six reported cases of a severe and rare kind of blood clot in individuals who received the Johnson & Johnson (Janssen) COVID-19 vaccine.
This comes after more than 6.8 million doses of the vaccine have been distributed across the country.
The blood clot, known as cerebral venous sinus thrombosis (CVST), was observed in combination with low levels of blood platelets (thrombocytopenia) among women between the ages of 18 and 48. Symptoms occurred 6 to 13 days after vaccination.
Usually, an anticoagulant drug called heparin is used to treat blood clots, but administration of heparin to treat this rare blood clot may be dangerous. Alternative treatments must be delivered.
On Wednesday, the CDC will convene a meeting of the Advisory Committee on Immunization Practices (ACIP) to investigate the potential importance of these cases. The FDA will then review that analysis as it also investigates the cases.
Until then, the FDA has recommended a pause in the use of this vaccine. That may ensure that providers can plan to manage potential cases with the unique treatment required for this type of blood clot.
At this time, these adverse events appear to be extremely rare, the FDA noted. However, people who have received the J&J vaccine that develop symptoms such as shortness of breath, severe headache, abdominal pain, or leg pain within three weeks after vaccination should contact their provider.
Additionally, the FDA asks health care providers to report adverse events post J&J vaccination to the Vaccine Adverse Event Reporting System.
“COVID-19 vaccine safety is a top priority for the federal government, and we take all reports of health problems following COVID-19 vaccination very seriously,” FDA wrote.
The CDC and the FDA are also expected to hold a media briefing on April 13 to provide additional information and answer questions. A recording of the briefing will be available on the FDA’s YouTube channel.
This comes after experts found dangerous blood clots in some AstraZeneca’s COVID-19 vaccine recipients last week. In response, Germany, France, Italy, and Spain have suspended the use of the vaccine.
AstraZeneca updated the safety of its vaccine in mid-March, noting that out of more than 17 million people vaccinated across the European Union and the UK with a AstraZeneca vaccine, there were just 37 reports of blood clots.
An FDA analysis from the end of February 2021 found that J&J’s COVID-19 vaccine met requirements for emergency use authorization based on a trial involving nearly 40,000 participants.
Specifically, the vaccine’s efficiency against moderate-to-severe COVID-19 was 66.9 percent 14 days after vaccination and 66.1 percent 28 days after vaccination.
Secondary analysis showed 76.7 percent vaccine efficiency against severe/critical COVID-19 14 days after vaccination and 85.4 percent 28 days after vaccination.