Find a registrant or pharmacy

Find a registrant Find a pharmacy

Search the website


Help me with...



Timing for administration of COVID-19 treatments and vaccines

November 10, 2021
Administration of vaccines should be delayed for at least 90 days after monoclonal antibody or convalescent plasma treatments.

Do you have patients seeking COVID-19 immunization after being treated for a COVID-19 infection? If so, please note the following message from Alberta Health Services:

The following is a message from Alberta Health Services:

COVID-19 vaccines should be delayed for at least 90 days after the receipt of SARS-CoV-2 monoclonal antibodies or convalescent plasma provided for treatment of COVID-19 infection. This applies to people who received these therapies before receiving any COVID-19 vaccine dose and between doses.

  • Timing of administration and potential interference between COVID-19 vaccine and monoclonal products or convalescent plasma as part of COVID-19 treatment are currently unknown and administering these products close together may result in less effectiveness of the COVID-19 vaccine.
  • A deferral for at least 90 days is based on the estimated half-life of such therapies and evidence suggesting that reinfection is uncommon within the 90 days after initial infection.
  • This is a precautionary measure until additional information becomes available, to avoid potential interference of the antibody therapy with vaccine-induced immune responses.
  • COVID-19 vaccine doses inadvertently received within 90 days after receipt of passive antibody therapy do not need to be repeated.

Timing of administration and potential interference between COVID-19 vaccine and monoclonal products not used for the treatment of COVID-19 infection are currently unknown and the primary care provider or medical specialist should be consulted on a case-by-case basis.

For more information on the Pfizer, Moderna, and AstraZeneca/COVISHIELD vaccines, visit the COVID-19 vaccine biological products pages from the Alberta Immunization Policy.