For Solid Organ Transplant Recipients, Does the Second Dose of SARS-CoV-2 mRNA Vaccine Make a Difference?

Recipients of solid organ transplants (SOT) mount poor antibody responses to the first dose of SARS-CoV-2 mRNA vaccine (NEJM JW Infect Dis Jul 2021) — however, data are limited regarding responses after the full two-dose vaccination. In this retrospective observational study from a single medical center in France, 143 SOT recipients (58 liver, 59 kidney, and 26 heart) and 25 health care workers (HCW; control group) received two doses of the Pfizer-BioNTech vaccine 28 days apart. IgG antibody titers to the receptor binding domain of the SARS-CoV-2 spike protein were measured at baseline and 28 days after the first and second doses. Median time from transplant to vaccination was 45 months. Titers <50.0 arbitrary units/mL were considered negat…