US Food and Drug Administration Limited use of Johnson & Johnson (Janssen) COVID-19 vaccine late Thursday, referring to a very rare but serious blood clotting disorder called thrombosis with thrombocytopenia syndrome (TTS).
From now on, the J&J vaccine is only to be used in people aged 18 and over who are unable or unwilling to receive another COVID-19 vaccine. That includes people who have had a life-threatening allergic reaction (anaphylaxis) to the COVID-19 mRNA vaccine, people who have personal concerns about the COVID-19 mRNA vaccines and would otherwise not get vaccinated, and people who do not have access to the mRNA COVID-19 vaccine.
The measure comes as the FDA and the Centers for Disease Control and Prevention monitor people who receive J&J’s COVID-19 vaccines for TTS. To date, agencies have identified and confirmed 60 cases of TTS linked to the vaccine, including nine deaths. That represents a rate of 3.23 TTS cases per million units of J&J vaccine administered, and a rate of 0.48 TTS deaths per million units of vaccine administered, the FDA said Wednesday.
Although the risks are small, the FDA has determined that they are unnecessary risks for most people to take, given the wide availability of mRNA vaccines (made by Moderna and Pfizer-BioNTech) that are equally effective and do not carry the same risks. big disease and death.
The FDA’s decision follows a decline recommendation from the Centers for Disease Control and Prevention Last December, it stated that the COVID-19 mRNA vaccines are preferred over the J&J vaccine. The CDC outlines specific situations in which the J&J vaccine may be considered, which matches the uses listed by the FDA.
Limits and risks
In a statement Wednesday, top vaccine regulator Peter Marks explained the timing of the FDA move. “We know that the Janssen COVID-19 vaccine also has a role in the current pandemic response in the United States and throughout the global community. Our action reflects our updated analysis of the risk of TTS following the administration of this vaccine and limits the use of the vaccine to certain populations,” he said, and “demonstrates the strength of our safety surveillance programs and our commitment to ensure that science and data Guide our decisions… The agency will continue to monitor the safety of the Janssen COVID-19 Vaccine and all other vaccines, and as has been the case throughout the pandemic, will evaluate New security information as well.”
TTS is a serious condition marked by an unusual combination of blood clots that block a blood vessel, aka thrombosis, and thrombocytopenia, a low total amount of blood platelets, which help blood clot. The condition can be especially dangerous if the blood clot affects the brain, as in a coronary artery thrombosis (CVST), which is a rare but life-threatening type of blood clot that prevents blood to drain from the brain.
The TTS risk from the J&J vaccine — which uses an adenovirus-based vaccine design — was first identified in early April 2021, at which point the CDC stopped using the vaccine. The FDA and CDC lifted the suspension later that month after determining that the vaccine’s benefits in preventing COVID-19 outweighed the small risk of developing TTS. It is still unclear how the vaccine may cause the condition in rare cases, however researchers hypothesize that something about the adenovirus-based vaccine may trigger an immune response that leads to platelet activation and low platelet levels. Another adenovirus-based COVID-19 vaccine, made by AstraZeneca, has also been linked to rare cases of TTS.
Between the TTS reports, the CDC delay, and early clinical trial data showing that mRNA vaccines outperformed the J&J vaccine, the use of the adenovirus-based vaccine has faltered in the US. Of the 577 million doses administered to date, only 18.7 million contain J&J vaccines.