CDC group weighs third blow for immunocompromised people

CDC advisory group examines whether fully vaccinated Americans with weakened immune systems need a booster dose of a Covid vaccine after data shows they are less likely to have antibodies to fight disease and more likely to suffer from a so-called revolutionary infection.

Immunocompromised populations account for 44% of hospitalized breakthrough cases of Covid – an infection in a fully vaccinated individual, according to a slide presented at the agency’s Vaccination Practices Advisory Committee meeting on Thursday. The segment of the population, which includes cancer patients, HIV patients, or those who have had organ transplants, only represents about 2.7% of the US adult population, according to the presentation.

The Centers for Disease Control and Prevention advisory committee is also meeting to discuss the safety profile of the Johnson & Johnson vaccine.

People who are immunocompromised are more likely to become seriously ill from Covid and are at a higher risk of passing the virus on to family and friends, the agency said.

Studies suggest that a third dose of the vaccine may help patients whose immune systems don’t respond as well to a first or second dose. Four small studies cited by the CDC showed that 16% to 80% of people with weakened immune systems did not have detectable antibodies to fight Covid after two injections.

Among immunocompromised patients who did not have a detectable antibody response, 33 to 50% developed an antibody response after receiving an additional dose, according to the CDC.

“Emerging data suggests that an additional dose of COVID-19 vaccine in immunocompromised people improves the antibody response and increases the proportion of those who respond,” according to a slide presented at the meeting.

The meeting comes as federal officials say that booster doses of vaccines for the general population are not needed at this time.

The advisory committee cannot recommend additional injections for anyone until the Food and Drug Administration grants full approval for the Covid vaccines or changes emergency use authorizations.

Other countries, such as France, are already distributing third injections to people with cancer or other immune deficiencies. The CDC group has previously said that the most vulnerable Americans, such as the elderly or transplant recipients, may need an extra dose.

Some doctors have been pushing for the United States to allow immunocompromised populations to receive an extra dose, according to Dr Dan Barouch, an immunologist at Harvard Medical School who helped develop the J&J vaccine.

“The most difficult people to vaccinate are those who are immunocompromised,” he said, adding that early data shows that a third injection can be safe and effective for these populations.

– CNBC’s Rich Mendez and Robert Towey contributed to this article.