A US government-appointed panel of medical experts on Thursday unanimously recommended mRNA Covid vaccines made by Pfizer and Moderna over Johnson & Johnson's shot, in light of its weaker protection and greater risks.
The panel voted 15-0 in favor of the new guidance, which applies to everyone over 18 years of age.
Centers for Disease Control and Prevention (CDC) director Rochelle Walensky is expected to sign off on the measure, officially steering the public away from J&J's drug, which was initially praised because it could be stored at fridge temperature and offered good efficacy against earlier strains of the coronavirus after just one shot.
But evidence later emerged linking it to a rare form of clotting, particularly among women of child-bearing age, causing authorities to briefly halt and then resume its use in April. It has remained a distant third choice of vaccine for Americans ever since.
This week, the Food and Drug Administration found the rate of this effect was higher than previously thought, and not confined to females.
Preliminary lab testing data has also suggested the jab offers very little protection against the new Omicron variant -- at least against infection.
"I would not recommend a Janssen vaccine to my family members," said Beth Bell, a clinical professor at the University of Washington, referring to the vaccine by the name of the J&J subsidiary that developed it.
"On the other hand, I think we do have to recognize that different people make different choices and if they are appropriately informed, I don't think we should remove that option," she added, explaining her vote.
- Nine deaths -
The CDC called the vote in light of concerning new safety data.
At least nine people have died from clotting with low platelets or Thrombosis with Thrombocytopenia Syndrome (TTS) as of December 9, with around 16 million doses of the vaccine administered, according to new data released by the CDC.
There were 54 cases as of August 31, and 36 required admission to intensive care. Some of those who did not die had long-term effects such as paralysis.
The greatest risks were seen in women aged 30-49, where the rate of TTS was around one in 100,000.
But the risk is not confined to this demographic, with two of the nine deaths occurring among men. The CDC said the fatality count may also be an underestimate.
Overall, approximately one out of seven cases of TTS have been fatal. Similar cases have been linked to the AstraZeneca vaccine, which is authorized outside the United States and is based on the same viral vector technology.
CDC scientist Sara Oliver told a committee of independent experts there were several options available to them, including voting to recommend against using the vaccine altogether.
But the panel of experts agreed that the J&J vaccine should remain available to people who for whatever reason might refuse mRNA vaccines, despite their higher efficacy and lower risks.
The Pfizer and Moderna vaccines carry risks too, the CDC said in its discussion of risks and benefits, particularly for younger men who may in very rare cases develop myocarditis or pericarditis -- inflammation of or around the heart.
However, none of these cases have been fatal, and the two vaccines confer much higher protection than the J&J shot.
The panel also agreed with the company that recommending against the J&J shot entirely would send a negative signal to other parts of the world where it may be the only option available.
"The Johnson and Johnson Covid-19 vaccine is a life saving tool for individuals in high risk populations," Penny Heaton, global therapeutic area head of vaccines at J&J argued.
(Except for the headline, this story has not been edited by NDTV staff and is published from a syndicated feed.)
