The U.S. Food and Drug Administration (FDA), Centers for Disease Control and Prevention (CDC) and Western States Scientific Safety Review Workgroup have all recommended an additional dose of mRNA COVID-19 vaccine be administered to people with moderately to severely compromised immune systems.
On Aug. 12, the U.S. Food and Drug Administration (FDA) adjusted the existing Emergency Use Authorizations (EUA) for the Pfizer and Moderna COVID-19 vaccines to allow certain immunocompromised people to receive a third, additional dose of vaccine.
“The country has entered yet another wave of the COVID-19 pandemic, and the FDA is especially cognizant that immunocompromised people are particularly at risk for severe disease,” said Acting FDA Commissioner Janet Woodcock, M.D. “After a thorough review of the available data, the FDA determined that this small, vulnerable group may benefit from a third dose of the Pfizer-BioNTech or Moderna Vaccines.”
For the purposes of this announcement, the FDA decision refers to “additional doses” of vaccine in individuals thought not to have an adequate immune response following a primary vaccine series. “Boosters,” or doses administered to individuals who had adequate immune responses but thought to have a waning response with time, were not the topic of this FDA decision for authorization.
Under the adjusted EUA guidelines, “immunocompromised individuals” are defined as solid organ transplant recipients or others who have similar reductions in their immune response.
The Centers for Disease Control and Prevention’s (CDC) Advisory Committee on Immunization Practices (ACIP) — made up of medical and public health experts who develop recommendations on the use of vaccines in the US — met Aug. 13 to provide further recommendations on the FDA’s decision.
During its meeting, the ACIP unanimously voted to adopt the FDA’s adjusted EUA that would allow immunocompromised individuals who complete a two-dose mRNA vaccine series (Pfizer or Moderna) to receive an additional dose of an mRNA vaccine.
The ACIP also expanded the FDA’s definition of “immunocompromised individuals” to include people who:
- Are undergoing active treatment for solid tumor and hematologic malignancies
- Have received solid-organ transplant and are taking immunosuppressive therapy
- Have received CAR (chimeric antigen receptor)-T-cell or hematopoietic stem cell transplant (within two years of transplantation or are taking immunosuppression therapy)
- Have moderate or severe primary immunodeficiency (e.g., DiGeorge, Wiskott-Aldrich syndromes)
- Have advanced or untreated HIV infection
- Are undergoing active treatment with high-dose corticosteroids (i.e., ≥20mg prednisone or equivalent per day), alkylating agents, antimetabolites, transplant-related immunosuppressive drugs, cancer chemotherapeutic agents classified as severely immunosuppressive, TNF blockers, and other biologic agents that are immunosuppressive or immunomodulatory
The full list of conditions can be found here. Following its meeting, ACIP sent its recommendations to CDC Director Rochelle P. Walensky, MD, MPH who signed and endorsed the recommendations later that day.
“This official CDC recommendation — which follows FDA’s decision to amend the emergency use authorizations of the vaccines — is an important step in ensuring everyone, including those most vulnerable to COVID-19, can get as much protection as possible from COVID-19 vaccination,” said Director Walensky in an Aug. 13 media statement.
Following Director Walensky and the CDC’s decision, the Western States Scientific Safety Review Workgroup convened to discuss implications of the adjusted EUA in Oregon.
The Western States Scientific Safety Review Workgroup — the group of nationally acclaimed immunizations and public health scientists independently reviewing the safety and efficacy of all FDA authorized COVID-19 vaccines for California, Nevada, Oregon and Washington — endorsed the FDA and CDC recommendations as well.
“To provide maximal protection to this vulnerable population, the Workgroup reiterates its recommendation that all persons 12 years and older, especially those with moderate to severe immunosuppression and those who are in close contact with them, receive an initial complete series of an authorized COVID-19 vaccine,” said the members of the workgroup in an official media statement. “Moreover, persons with moderate to severe immunosuppression who have received a complete series should receive an additional dose of an mRNA COVID-19 vaccine, based on current limited data on the safety and immunogenicity of an additional dose.”
According to the FDA’s updated EUA:
- A third dose of the Pfizer vaccine may be administered at least 28 days following the second dose of a two-dose regimen to immunocompromised individuals ages 12 and older.
- A third dose of the Moderna vaccine may be administered at least 28 days following the second dose of a two-dose regimen to immunocompromised individuals ages 18 and older.
The additional shot recommendation only applies to individuals who are considered immunocompromised per the adjusted EUA language.
Under current conditions, the CDC and ACIP do not recommend administering additional doses of the COVID-19 vaccines to individuals who are not included in the immunocompromised definition. Additional doses recommended by a doctor to people who do not meet the immunocompromised criteria for this EUA should be discussed directly with the manufacturer and FDA.
Vaccines given according to the currently recommended schedule continue to be highly effective in reducing the risk of serious illness from COVID-19. Observational data confirm that currently available vaccines are effective against new variants, including the Delta variant.
Folks who believe they are eligible for an additional dose of an mRNA vaccine based on the conditions outlined in the adjusted EUA should talk with their health care provider to learn more. To monitor the safety of additional doses, the Workgroup continues to encourage all recipients of COVID-19 vaccine with access to a smartphone to participate in the v-safe program.
While an additional dose of mRNA vaccine is likely to increase protection in moderately to severely immunocompromised individuals, people who receive a third dose should continue to wear a mask, stay six feet apart from others, and avoid crowds and poorly ventilated indoor spaces.
Further recommendations regarding additional doses for immunocompromised individuals can be found on the interim clinical recommendations released by the CDC.