Moderately and severely immunocompromised people 12 or older who completed an mRNA COVID-19 vaccine primary series and received an additional mRNA vaccine dose should receive a single COVID-19 booster dose (Pfizer-BioNTech, Moderna or Janssen) at least 5 months after completing their third mRNA vaccine dose. In such situations, people who are moderately and severely immunocompromised may receive a total of four COVID-19 vaccine doses.

Moderately and severely immunocompromised people 18 or older who received a single dose Janssen COVID-19 vaccine primary series should receive a single COVID-19 booster vaccine (Pfizer-BioNTech, Moderna or Janssen) at least 2 months (8 weeks) after receiving their initial Janssen primary dose. A person who received one primary dose of Janssen COVID-19 vaccine should not receive more than two COVID-19 vaccine doses.

A patient’s clinical team is best positioned to determine the appropriate timing of vaccination.