JNJ the comeback kid Johnson & Johnson's Covid-19 vaccine worked better than it gets credit for and may play an important role in the future | CNN
The mRNA vaccine technology has been shown to quickly elicit a potent and robust immune response after vaccination, but that can wane over time. Johnson & Johnson’s virus-vector platform may not spark as powerful of an immune response in the short term, but it is known to have strong durability.
“Over time, the efficacy of the Pfizer and Moderna vaccines goes down, the efficacy of the J&J vaccines remains stable, and so it is exactly as you would predict: that they will converge and they will then cross,” Barouch said.
The J&J vaccine also might have “a particular edge,” he said.
“The immune system is actually made of two arms: the antibodies side and the T cells. And the type of T cells that are critical for prevention of serious illness are called CD8 T cells,” Barouch said. “The J&J vaccine raises better CD8 T cells than the Pfizer and other mRNA vaccines, so the J&J vaccine might have a particular edge for variants like Omicron that largely escaped from antibody responses.”
Overall, Barouch called this data “very reassuring” for recipients of the J&J vaccine.
“They should be reassured that they received a vaccine that gives very good protection for a long period of time,” Barouch said. “And I think the second message is that I think people should learn about these new data in terms of considering booster shots, as well.”
Prospects as a booster?
David Montefiori, a virologist at Duke University Medical Center, said “the J&J vaccine has kind of gotten a bad rap because of the efficacy, but the stability of the response is intriguing.”
The antibody level went down with every vaccine during the Omicron surge, and that could mean people need an additional booster. More research is needed to find out.
A yet-unpublished study by the National Institutes of Health looking at a mix-and-match vaccine strategy saw good results when J&J was included, Montefiori said.
Get CNN Health’s weekly newsletter
Sign up here to get The Results Are In with Dr. Sanjay Gupta every Tuesday from the CNN Health team.
“In people who got the Pfizer vaccine initially and then a boosted with the J&J vaccine, those people made pretty high levels of neutralizing antibodies to Omicron: 10 times higher than people who got two shots with just the J&J vaccine,” he said. “So the J&J vaccine might be a good booster for people who got an mRNA vaccine initially.”
The Johnson & Johnson vaccine can be used for primary doses or as a booster, but the CDC says the Pfizer and Moderna vaccines are recommended in most situations because of the risk of serious adverse events with the Johnson & Johnson vaccine.
The J&J vaccine has been linked to rare cases of blood clots with low platelets, known as thrombosis with thrombocytopenia syndrome or TTS. “It occurs at a rate of about 3.83 cases per million Janssen doses and has resulted in deaths,” the CDC says.
Dr. Angela Branche, an infectious disease specialist and associate professor of medicine at the University of Rochester, said the side effect profile of the J&J vaccine “remains something that’s of concern for some groups where that risk is high.” Women ages 30 to 49 years are at increased risk of this rare adverse event, the CDC says.
But if that research pans out, the J&J vaccine may be useful as a booster for only certain populations.
“For some groups where that risk of developing serious blood clots is not very high, like older adults, this may be a good strategy,” Branche said.
Montefiori said the vaccine deserves more study.
“I think there might still be a place for the J&J vaccine in the long-term picture of this pandemic,” Montefiori said.
