Lauren Dempsey, MS in Biomedicine and Law, RN, FISM News
This week the FDA announced it was limiting the use of Johnson & Johnson’s Janssen COVID-19 vaccine due to the risk of developing a rare blood clotting disorder. The vaccine was approved in February 2021 for individuals 18 years and older and can be administered in a one or two-dose series. However, the FDA is recommending that the J&J vaccine only be administered if mRNA vaccines are not available, medically appropriate, or if a person is less likely to use the other available vaccines.
In April 2021 the FDA investigated reports of thrombosis with thrombocytopenia syndrome (TTS), a rare and potentially life-threatening syndrome that causes blood clots as well as low levels of blood platelets usually within one to two weeks following vaccination. A total of 15 TTS cases were confirmed that could be linked to vaccination out of 8 million doses that had been administered. Following this discovery, the agency placed a pause on its use and the CDC and ACIP recommended the mRNA vaccines over the J&J vaccine. The FDA eventually decided to limit the use of the vaccine for special circumstances.
Dr. Peter Marks, director of the FDA’s Center for Biologics Evaluation and Research said “We recognize that the Janssen COVID-19 vaccine still has a role in the current pandemic response in the United States and across the global community. Our action reflects our updated analysis of the risk of TTS following administration of this vaccine and limits the use of the vaccine to certain individuals.” He also added that the “action demonstrates the robustness of our safety surveillance systems and our commitment to ensuring that science and data guide our decisions,” and most importantly guarantees that 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 thoroughly evaluate new safety information.”
While the FDA chose to investigate and put restrictions on the J&J vaccine due to very rare side effects, the agency also investigated but largely dismissed, the link between myocarditis and pericarditis after mRNA vaccine administration, even after multiple Nordic countries halted the use of Moderna vaccines due to the increased risk. U.S. agencies and public health officials have stayed firm in their stance that the benefits associated with vaccination outweigh any potential risks.
Interestingly, an analysis published in Scientific Reports identified a correlation between Israel’s mandatory vaccination roll-out with an increase in EMS (911) calls. The report showed that COVID-19 vaccination was “significantly associated” with a 25 percent increase in these calls, specifically for cardiac-related events in 16-39 year old’s. The authors of the report state that this data highlights the “causal relationship between vaccines and myocarditis, a frequent cause of unexpected cardiac arrest in young individuals.”
There are still many unknowns related to the cause of blood clots and heart issues post-vaccination, however, a team of German researchers believes that it is the mechanism of action that triggers a response. The J&J vaccine is a viral vector vaccine, while the Pfizer and Moderna vaccines are mRNA vaccines. Researchers believe that viral vector vaccines, which use modified viruses to transfer genetic material through vaccination, could result in an autoimmune response leading to blood clots. The dilemma is, that there is no way to tell who will react and who won’t.
The risk for TTS is about three cases for every 1 million doses of vaccine administered, and there are still no known causes or contributing factors for developing the disorder. While rare, those with TTS “may rapidly deteriorate, despite prompt diagnosis and treatment,” the FDA said and added that clots “can lead to long-term and debilitating health consequences,” including a high risk for death.