FDA Panel Backs Second Shot for Those Who Got J&J Vaccine

Oct. 15, 2021 — A FDA advisory committee on Friday voted 19-0 to authorize second doses of the Johnson & Johnson COVID-19 vaccine in an effort to boost immunity. It was the second vote in as many days to back a change to a COVID vaccine timeline.

In its vote, the committee said that boosters could be offered to people as young as age 18. However, it is not clear that everyone who got a Johnson & Johnson vaccine needs to get a second dose.  The same panel voted Thursday to recommend booster shots for Moderna vaccine, but for a narrower group of people.

It will be up to a CDC panel next week to make more specific recommendations for who might need another shot. The CDC’s Advisory Committee on Immunization Practices is scheduled to meet next Thursday to discuss issues related to COVID-19 vaccines.

Studies of the effectiveness of the J&J vaccine in the real world show that its protection — while good — has not been as strong as the mRNA vaccines made by Pfizer and Moderna, which are given as part of a two-dose series.

Limited Data

The company presented data from six studies to the FDA panel in support of a second dose were limited. The only study looking at second doses after 6 months included just 17 people.

These studies did show that a second dose substantially increased levels of neutralizing antibodies, which are the body’s first line of protection against COVID-19 infection.

But the company turned this data over to the FDA so recently that agency scientists repeatedly stressed during the meeting that they did not have ample time to follow their normal process of independently verifying the data and following up with their own analysis of the study results.

Peter Marks, MD, director of the FDA’s Center for Biologics Evaluation and Research, said it would have taken months to complete that rigorous level of review.

Instead, in the interest of urgency, the FDA said it had tried to bring some clarity to the tangle of study results presented that included three dosing schedules and different measures of effectiveness.

 “Here’s how this strikes me,” said committee member Paul Offit, MD, a professor of pediatrics and infectious disease at Children’s Hospital of Philadelphia. “I think this vaccine was always a two-dose vaccine. I think it’s better as a two-dose vaccine. I think it would be hard to recommend this as a single-dose vaccine at this point.”

Who Needs a Second Dose?

Thursday, the committee heard an update on data from Israel, which saw a wave of severe breakthrough infections during the Delta wave. 

COVID-19 cases are falling rapidly there after the country widely deployed booster doses of the Pfizer vaccine.

On Friday, the Marks from the FDA said the agency was leaning toward creating greater flexibility in the emergency use authorizations for the Johnson & Johnson and Moderna vaccines so that boosters could be more widely deployed in the U.S., too.

The FDA panel on Thursday voted to authorize a 50-milligram dose of Moderna’s vaccine — half the dose used in the primary series of shots — to boost immunity at least 6 months after the second dose. Those who might need a booster are the same groups who’ve gotten a green light for third Pfizer doses, including people over 65, adults at higher risk of severe COVID-19 and those who are at higher risk because of where they live or work.

Others pointed out that preventing even mild to moderate infections was a worthy goal, especially considering the implications of long-haul COVID-19

“COVID does have tremendous downstream effects, even in those who are not hospitalized. Whenever we can prevent significant morbidity in a population, there are advantages to that,” said Steven Pergam, MD, medical director of infection prevention at the Seattle Cancer Care Alliance.

“I’d really be in the camp that would be moving towards a younger age range for allowing boosters,” Pergam said.