CDC formally recommends third vaccine dose for immunocompromised people

The CDC’s recommendation, which advises health care providers on how to implement the FDA’s update, spells out in more detail who should be considered “moderately to severely” immunocompromised. Such patients include those receiving active treatment for cancerous tumors or blood cancer, recipients of stem cell transplants within the last two years, those with advanced or untreated HIV and those taking drugs that may suppress the immune system.

FDA’s update left the task of firming up the definition of “immunocompromised” to the CDC panel and to individual doctors. Despite CDC’s additional guidance, it is not clear how some providers will decide when to give a third shot. CDC committee member Camille Kotton, who runs a transplant clinic at Massachusetts General Hospital, noted that she expects immunocompromised patients to begin seeking additional doses as soon as this weekend.

Americans seeking out an additional Covid-19 vaccine dose won’t need a prescription or doctor’s note to obtain one, raising questions about how vaccine providers will discern who is truly eligible. Pharmacists may ask patients whether they have eligible moderate or severe conditions, but they only need to “self-attest,” the CDC’s Kathleen Dooling said.

The CDC aims to provide guidance to health care providers about who those individuals are while allowing some flexibility for them to assess whether the patients’ immunosuppression is moderate or severe, said Amanda Cohn, senior adviser for vaccines at the CDC’s National Center for Immunization and Respiratory Diseases. Residents of long-term care facilities and people with diabetes or heart disease “are not the intent here,” she said.

Members of the CDC panel couched their recommendation for a third shot as an updated initial dosing regimen — rather than a booster shot — for those who may not have mounted a sufficient immune response after the initial two-dose series. While panel members said eligible people should to stick to the vaccine brand they initially received if possible, switching to the other type is allowed.

In all cases, people eligible for a third shot should wait at least 28 days after completing their first two doses.

Peter Marks, FDA’s top vaccine adviser, cautioned that a third dose in these patients may be only “moderately effective” at boosting their immune response to the vaccine. These people should maintain physical mitigation measures like masking, distancing and avoiding crowded indoor spaces even after the third shot, health officials said, and their close contacts are encouraged to be fully vaccinated against Covid.

The CDC’s Dooling said the agency and the FDA “are actively engaged” to ensure that immunocompromised recipients of the Johnson & Johnson vaccine, which lacked enough data to support an expansion of its EUA, “have optimal vaccine protection.”

“We had to do what we’re doing based on the data we have in hand,” Marks said, adding that public health officials believe they’ll have a “solution” for what’s believed to be a very small number of immunocompromised J&J recipients “in the not-too-distant future.”

Federal officials have said that they believe few immunocompromised people got the J&J shot, given that many were among the first in line for vaccination and the J&J vaccine was approved well after the Pfizer and Moderna options.

The Centers for Medicare and Medicaid Services didn’t wait for the CDC panel’s vote, stating Friday morning that immunocompromised Medicare patients may receive an extra vaccine dose at no cost.

The panel also discussed how it will approach evaluating whether and when the rest of the population may need booster doses as vaccine-induced immunity wanes and variants continue to emerge. The CDC committee’s next meeting, on Aug. 24, will focus on studying data on boosters. The panel is expected to convene regularly over the coming weeks to solidify its process for deciding on when boosters are necessary and for whom.

The elderly, health care workers and long-term care residents will be the first populations assessed for booster need, as they were the first to get vaccinated, the CDC’s Sara Oliver said.

Any consideration of boosters must focus on preventing severe illness, hospitalization and death, Oliver said, as opposed to precluding infection at all. Global vaccine equity is another consideration, she said, noting that variants can emerge from regions with low vaccine coverage and high transmission.