Immunocompromised individuals, such as solid organ transplant (SOT) recipients are at high risk of COVID-19 associated complications and mortality. Retrospective studies so far have shown that a majority of SOT recipients did not develop appreciable anti-spike antibody response after a first, second, or even third dose of mRNA vaccine. Treatment with antimetabolites was associated with poor vaccine response. The goal of this study is 1) examine whether transient immunosuppression reduction improves the immune response to a third dose of SARS-CoV-2 mRNA vaccine in kidney transplant recipients and 2) to assess the safety of immunosuppression reduction before and after third dose SARS-CoV-2 mRNA vaccination.

This is a prospective, randomized open-labeled study of kidney transplant recipients who have previously received two doses of mRNA COVID-19 vaccine (either BNT162b2, Pfizer-BioNTech or mRNA-1273, Moderna) and who are eligible to receive a 3rd dose of mRNA vaccine.

Inclusion Criteria:

• Participant is willing and able to give informed consent for participation in the study
• First or repeat kidney transplant recipient
• Negative or low positive antibody titer on SARS-CoV-2 antibody assay
• On a mycophenolate or azathioprine based immunosuppressive regimen
• > 6 months post-transplant

Exclusion Criteria:

• Pregnancy
• Contraindication to SARS-CoV-2 vaccination (severe allergic reactions or anaphylaxis)