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IAC summarizes August 13 ACIP meeting on new recommendation for additional dose of mRNA COVID-19 vaccine for people with moderate to severe immunocompromise

On August 13, the Advisory Committee on Immunization Practices (ACIP) met to review the FDA’s August 12 modifications to its Emergency Use Authorizations (EUAs) for the Pfizer-BioNTech and Moderna mRNA COVID-19 vaccines. ACIP members unanimously recommended administration of an additional dose of mRNA vaccine for moderately to severely immunocompromised people who have completed either 2-dose mRNA COVID-19 vaccine series. This recommendation does not apply to immunocompromised people who received Janssen COVID-19 Vaccine (Johnson & Johnson). Presentation slides from the meeting are available online, and details of this recommendation are provided below. 

Background: Approximately 7 million people (2.7% of the population) in the United States are immunocompromised. These individuals are more likely to get severely ill from SARS-CoV-2 infection and shed the virus for prolonged periods. Small studies indicate that, when compared to non-immunocompromised people, immunocompromised people are more likely to have serious breakthrough infection; 40–44% of fully vaccinated individuals hospitalized with breakthrough infection have been immunocompromised. A blood test showing detectable neutralizing antibodies after vaccination is a simple but imperfect estimate of a person’s protection from COVID-19 illness. Among immunocompromised people with no detectable antibody response to a 2-dose mRNA vaccine series, 33–50% developed a detectable antibody response after a third dose. 

Available evidence supports the conclusion that an additional dose is safe in immunocompromised people. Public health authorities in other countries, including France, Israel, Germany, and the United Kingdom, have recommended an additional dose of COVID-19 vaccine be given to immunocompromised people. 

CDC presenters emphasized the difference between an additional dose in this context and a booster dose. An “additional” dose of vaccine is a dose administered when the immune response to a standard primary vaccine series is likely not to be protective. A “booster” dose of vaccine is a dose administered to restore protection after the effectiveness of protection from the primary series has declined. ACIP does not recommend booster doses at this time. 

Implementation and Clinical Considerations: Following approval of the ACIP recommendation, CDC updated its Interim Clinical Considerations for Use of COVID-19 Vaccines Currently Authorized in the United States. COVID-19 vaccine providers should review this CDC document carefully for complete information. Highlights of key aspects of implementation guidance for this recommendation are provided below.

Moderately to Severely Immunocompromised People: The ACIP recommendation applies to people with moderate to severe immunocompromise due to a medical condition or immunosuppressive treatment. According to CDC, these conditions and treatments include but are not limited to:

• Active treatment for solid tumor and hematologic malignancies
• Receipt of solid-organ transplant and taking immunosuppressive therapy
• Receipt of CAR-T-cell or hematopoietic stem cell transplant (within 2 years of transplantation or taking immunosuppressive therapy)
• Moderate or severe primary immunodeficiency (e.g., DiGeorge syndrome, Wiskott-Aldrich syndrome)
• Advanced or untreated HIV infection
• Active treatment with high-dose corticosteroids (i.e., 20 mg or more prednisone or equivalent per day), alkylating agents, antimetabolites, transplant-related immunosuppressive drugs, cancer chemotherapeutic agents classified as severely immunosuppressive, tumor-necrosis [factor] (TNF) blockers, and other biologic agents that are immunosuppressive or immunomodulatory.

The ACIP recommendation does not require vaccine providers to obtain a prescription or medical verification of a person’s condition; patients may simply attest to their immunocompromised status.  

Vaccine Type:

• The recommendation applies only to people who have completed a mRNA vaccine series. 
• When possible, the additional dose should be the same mRNA vaccine as the primary series. However, the other mRNA vaccine may be used if the primary series product is not available. 

Vaccination Timing: The additional dose of mRNA COVID-19 vaccine should be administered at least 28 days after the second dose. 

Age Range: Age groups authorized to receive the additional dose:

• Pfizer-BioNTech COVID-19 Vaccine: age 12 years and older
• Moderna COVID-19 Vaccine: age 18 years and older  

Patient Counseling: Immunocompromised people should continue to practice the same COVID-19 infection prevention measures as unvaccinated people (e.g., mask wearing, social distancing, and avoiding crowds or poorly ventilated indoor spaces) because they may not be adequately protected from breakthrough illness even after receiving an additional dose.

Serologic Testing: Post-vaccination serologic testing is not part of this recommendation. The FDA has not approved a test for this purpose. 

Action Step: Update EUA Fact Sheets used in your clinic to current versions (see links below).

Additional Presentations: Following the vote described above, CDC updated the ACIP on COVID-19 epidemiology and vaccine effectiveness. Notably, as of August 2, among the more than 164 million fully vaccinated people in the U.S., there have been only 7,101 hospitalizations and 1,507 COVID-related deaths. The majority (75%) of hospitalized or fatal breakthrough cases were in people age 65 years and older.  

The day’s final presentation included background information for future policy discussions on booster doses (see definition above) of COVID-19 vaccines for immunocompetent people who have completed a primary series. 

Future ACIP Meetings: The next announced ACIP meetings are scheduled for August 24 (COVID-19 vaccines only), September 29–30 (catch-up on other vaccine-preventable diseases), and the regularly scheduled meeting on October 20–21. Additional meetings may be announced; information about past and future ACIP meetings may be found on the ACIP website. 

Related Links

• CDC: Interim Clinical Considerations for Use of COVID-19 Vaccines Currently Authorized in the United States 
• NEJM: Randomized Trial of a Third Dose of mRNA-1273 Vaccine in Transplant Recipients 
• CDC: Additional mRNA COVID-19 Vaccines for Moderately to Severely Immunocompromised People Clinician Outreach and Communication Activity (COCA) teleconference recording
• FDA: Emergency Use Authorization (EUA) fact sheets for healthcare providers administering COVID-19 vaccine (Pfizer-BioNTech, 8/12/21) (Moderna, 8/12/21) 
• FDA: Emergency Use Authorization (EUA) fact sheets for recipients and caregivers (Pfizer-BioNTech, 8/12/21) (Moderna, 8/12/21)
• FDA: COVID-19 Vaccine Frequently Asked Questions (Pfizer-BioNTech, 8/12/21) (Moderna, 8/12/21)
• CDC: COVID-19 Vaccine Recipient Education web page
• CDC: COVID Data Tracker