A person walks past a sign that reads “The vaccine is our best shot against COVID-19” on the Upper West Side amid the coronavirus pandemic in New York City on March 30, 2021.
Noam Galai | Getty Images
Johnson & Johnson privately asked Covid-19 vaccine rivals Pfizer and Moderna Participate in a study that looked at the potential risk of blood clots, but the companies refused The Wall Street Journal reported on Fridayciting persons who are familiar with the matter.
Pfizer and Moderna executives said theirs Vaccines seemed safe and they did not see the need to redouble efforts by regulators and companies already addressing the rare blood clot problem, the journal report said.
Only AstraZeneca, whose vaccine raised regulatory concerns about blood clots, agreed to join the effort, the Journal said.
CNBC has asked the four companies to comment.
On Tuesday the Food and Drug Administration and the Centers for Disease Control and Prevention did advised states to pause temporarily J & J’s use of the vaccine “out of caution” after six women developed a rare but potentially life-threatening bleeding disorder in which one was dead and one in critical condition.
The women developed a condition known as cerebral venous sinus thrombosis (CVST) within about two weeks of receiving the shot, US health officials told reporters. CVST is a rare form of stroke that occurs when a blood clot forms in the venous sinuses of the brain. It can eventually leak blood into the brain tissue and cause bleeding.
A CDC panel on Wednesday decided to postpone a decision on J & J’s use of vaccine while officials investigate the cases.