FDA panel supports J&J COVID-19 vaccine booster shot for all Americans who got a first dose

Johnson & Johnson's vaccine should be considered a two-dose vaccine rather than the one-and-done shot that had received initial authorization, a federal panel decided Friday.

The committee felt the 15 million Americans who got a single dose of the "one and done" J&J vaccine would be substantially better protected with a second one. 

“It was always going to be a two-dose shot," said Dr. James Hildreth, president of Meharry Medical College in Nashville.

The Vaccines and Related Biological Products Advisory Committee voted unanimously, 19-0, to support what J&J describes as a booster at least two months after the initial shot.

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Data from J&J and real-world experience show that the single shot provides less protection against COVID-19 than the Moderna and Pfizer-BioNTech vaccines, which are both two-dose regimens. Company studies suggest J&J's protection continues over time, while effectiveness against less severe disease appears to fade with the other two.

Committee members said they felt urgency to provide an extra dose of vaccine to people who received the single shot of J&J.

"There is a public health imperative here because what we're seeing is that this is a group with overall lower efficacy than we have seen with the mRNA vaccines. So there is some urgency there to do something," said committee chair Dr. Arnold Monto, a professor of epidemiology at the University of Michigan School of Public Health. 

In response to pointed questions by the committee, Dr. Penny Heaton, head of the vaccines global therapeutic area for Janssen Pharmaceuticals, a Johnson & Johnson company that developed the vaccine, agreed the effectiveness of their vaccine varied across study different groups, though it was "consistent and durable" within groups – in other words, it didn't decrease with time.

"However, because the magnitude is lower than I think what would be desired – the estimates that have been seen with the mRNA vaccines – there is headroom to improve the efficacy," she said. 

Adding a second dose 2- to 6-months after the initial J&J shot would provide the same effectiveness as the mRNA vaccines without their fading protection, Heaton told the committee Friday.

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J&J claims its vaccine is 75% effective worldwide against any infection and 70% effective at preventing severe disease and hospitalization. There were lower rates seen in other countries, J&J said, likely because of different variants circulating there. 

But surveillance by the Centers for Disease Control and Prevention has found that the J&J vaccine is only 68% effective against hospitalization in most adults. 

For all age groups, vaccine effectiveness is highest in Moderna vaccine recipients, at 95%, followed by Pfizer-BioNTech at 80% and J&J at 60%, a report published by the CDC on Sept. 17 found.

The two mRNA vaccines are more effective, even considering that their strength seems to wane over time, said Dr. Amanda Cohn, a vaccine expert with CDC’s National Center for Immunizations and Respiratory Diseases.

“There were some other data which showed that real-world effectiveness (for J&J) is hovering more in the 50 to 60% range,” she said. “The effectiveness or protection with a single dose of the J&J vaccine is not equivalent to protection with either two doses of an mRNA vaccine, and certainly not in those groups who have now been authorized to receive a booster dose of an mRNA vaccine."

"The contrast has not been stated so starkly before," said Dr. William Schaffner, a professor of preventive medicine at Infectious Diseases Vanderbilt University Medical Center in Nashville, who is not a committee member.

To counter the decline in effectiveness over time, the committee has already approved booster shots for people who received the Pfizer-BioNTech or Moderna vaccines and meet certain conditions. 

The committee decisions on both the Moderna and J&J supplementary shots still need to be verified by a different advisory panel as well as top federal officials. The CDC advisory panel is expected to meet Oct. 20 and 21 to discuss extra doses for Moderna and J&J recipients.

The CDC continues to recommend that people receive extra doses of the same vaccine they got the first time.

After the vote on the J&J second vaccine dose, the committee considered a study by the National Institutes of Health posted Wednesday which looked at mixing and matching booster doses of vaccine.

It included nearly 500 people and found that the J&J shot followed by either the Moderna or Pfizer vaccine as a booster produced a stronger immune response than two doses of J&J. For people who got either the Pfizer or Moderna two-dose series, a booster dose of either mRNA vaccine was effective.

The committee decided that more data was needed from the ongoing study before it could make any suggestions on whether to allow people to get a booster shot different from their original vaccine.

One dose of the J&J vaccine still counts as "full vaccination," according to the CDC. 

Government officials have said that the original doses of vaccine – one shot of J&J and two each of either Moderna or Pfizer-BioNTech – would continue to be considered "fully vaccinated" for the purposes of employment, travel and venue entry. 

About 15 million Americans have been fully vaccinated with the J&J vaccine, compared with 103 million who’ve gotten Pfizer and 69 million who’ve gotten Moderna. So far, 8.8 million Americans have received a booster dose of the Pfizer vaccine.

Contact Elizabeth Weise at eweise@usatoday.com and Karen Weintraub at kweintraub@usatoday.com.

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