COVID-19 Resource Center

COVID-19 Resource Center

Disclosures: Embi reports no relevant financial disclosures. Please see the study for all other authors’ relevant financial disclosures.
November 02, 2021
1 min read

Study supports extra doses of COVID-19 vaccine for immunocompromised patients

Disclosures: Embi reports no relevant financial disclosures. Please see the study for all other authors’ relevant financial disclosures.
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COVID-19 vaccination is less effective in immunocompromised adults than it is in the general population, a large study found, supporting recent recommendations that they receive extra doses.

In August, the FDA has authorized a third dose of COVID-19 messenger RNA vaccine for certain immunocompromised people — “specifically, solid organ transplant recipients or those who are diagnosed with conditions that are considered to have an equivalent level of immunocompromise.”

COVID vaccine stock image
Source: Adobe Stock.

Since then, the FDA has authorized booster doses for millions more people, and the CDC now says that immunocompromised people can receive a booster dose of COVID-19 vaccine 6 months after a third dose.

In the new study, which was published in MMWR, Peter J. Embi, MD, president and CEO of the Regenstrief Institute in Indianapolis, and colleagues evaluated mRNA vaccine efficacy among immunocompromised adults using data from the VISION Network, a collaboration between the CDC and seven U.S. health care systems. Data came from adults hospitalized with COVID-19-like symptoms from Jan. 17 through Sept. 5 in 187 hospitals in nine states.

They evaluated vaccine effectiveness against COVID-19-associated hospitalization using a test-negative design that compared 20,101 immunocompromised adults — 53% of whom received a two-dose mRNA COVID-19 vaccine series — with 69,116 immunocompetent adults, 43% of whom were fully vaccinated with a two-dose mRNA series.

Vaccine effectiveness was 77% (95% CI, 74%-80%) among immunocompromised adults compared with 90% (95% CI, 89%-91%) among those who are immunocompetent, the researchers reported.

The difference in efficacy persisted no matter which mRNA patients received, their age, timing of hospitalization or predominance of the delta variant.

Additionally, efficacy differed among immunocompromised subgroups, such as those who received an organ or stem cell transplant (59%) compared with those with a rheumatologic or inflammatory disorder (81%).

“Immunocompromised persons benefit from and should receive COVID-19 vaccines,” the authors wrote. “Given that [vaccine effectiveness] is lower compared to immunocompetent patients, immunocompromised persons receiving mRNA vaccines should receive three doses and a booster 6 months after the third dose, consistent with CDC recommendations.”