Improved humoral immunogenicity with mRNA‐1273 versus BNT162b2 as third vaccine dose among solid organ transplant recipients seronegative after two BNT162b2 doses.

Fewer than 45% of solid organ transplant recipients (SOTRs) mount a detectable antispike antibody level after two doses of mRNA SARS-CoV-2 vaccination (D2).1 Various vaccination strategies, including mixing platforms, have been proposed, but there is no consensus on the optimal vaccination sequence to improve immunogenicity.2,3 Although using similar technology, the mRNA-1273 vaccine has been associated with higher peak antibody responses than the use of BNT162b2 in immunosuppressed populations, potentially related to a higher vaccine antigen dose.3,4 We therefore studied whether the use of mRNA-1273 versus BNT162b2 as a third primary vaccine dose (D3) might generate a more robust antibody response in SOTR who remained seronegative after two doses of BNT162b2. Improved humoral immunogenicity with mRNA-1273 versus BNT162b2 as third vaccine dose among solid organ transplant recipients seronegative after two BNT162b2 doses METHODS From our national observational study, approved by the Johns Hopkins Institutional Review Board (IRB00248540),4 we included adult SOTRs who tested seronegative after two doses of BNT162b2 and received either a D3-BNT162b2 or D3-mRNA-1273. [Extracted from the article]