COVID-19 Vaccines: Additional Dose and Boosters 

There are two different ways to consider the need for additional vaccine doses in an individual or population. Both are currently components of the Centers for Disease Control and Prevention (CDC) guidance related to COVID-19.

What is a booster versus an additional dose?

• Additional dose: An additional dose refers to a vaccine dose that is given to an individual when the primary dose may not result in enough of an immune response (antibodies needed).  Studies such as CORALE-IBD, PREVENT-COVID, ICARUS and HERCULES IBD have shown that the vast majority of patients with IBD are seropositive post immunization. 


• Booster dose: A booster dose refers to a vaccine dose that is given to an individual if the primary dose did result in enough of an immune response (antibodies needed), but is likely to decrease over time.  The CDC has updated their recommendations to include a second booster (mostly mRNA preferred, but Johnson & Johnson vaccine may be considered in specific situations).

Who is eligible for either—or both? 

Eligibility requirements may be updated regularly by the CDC. Please check back for updates. 

For IBD patients, an additional dose may be considered for patients who are immunocompromised as defined by those receiving these immune therapies (thiopurines (azathioprine, 6-mercaptopurine, Azasan, Imuran, Purinethol), methotrexate (Trexall), prednisone, anti-TNF therapies including infliximab (Remicade, Inflectra, Remsima), adalimumab (Humira), certolizumab pegol (Cimzia), and golimumab (Simponi)). 

Patients receiving vedolizumab (Entyvio) or ustekinumab (Stelara) are not considered immunocompromised. 

Although studies in IBD have not shown an insufficient immune response to the vaccine, they are certainly eligible based on guidance from the CDC.  We encourage patients to discuss the need for additional dose and/or booster with their doctor. 

Booster dose: The CDC and FDA have authorized boosters for all adults age 12 and older, 5 months after an mRNA vaccine or 2 months after Johnson & Johnson vaccine for a first booster. Second boosters are considered for patients at least after 4 months of the previous booster dose. 

Do IBD patients need an additional dose? 

Most IBD patients are not considered immunocompromised and ongoing research is showing that patients develop the sufficient antibodies intended from the COVID-19 vaccines. If you are taking immune therapies as outlined above, you should consider your level of risk and discuss with your doctor whether or not you need an additional dose of the vaccine (mRNA only). Immune suppressing therapies include the following:  

• High-dose systemic corticosteroids (defined as ≥20mg/day of oral prednisone) 
• Anti-TNF biologics and biosimilars 
• Immunomodulators (azathioprine, methotrexate, etc.) 

Remember, an additional dose is intended for those who have weakened immune systems. This is different than a booster dose which may be recommended within a longer timespan for a broader population who did mount an appropriate immune response. 

Can I mix and match doses? 

The FDA updated its approvals of the COVD-19 vaccines to allow for a mix-and-match approach to booster doses. People who had received the Johnson & Johnson vaccine may receive a booster dose from the other available vaccines, such as the Pfizer vaccine or the Moderna vaccine. More information can be found in the following FDA update.

Last updated: 5/18/22 for Vaccine booster ages 5-11