A fourth dose of mRNA-based vaccine may be warranted in some kidney transplant recipients

A case series published in Annals of Internal Medicine finds that a fourth dose of an mRNA-based vaccine produces a satisfactory antibody response in some kidney transplant recipients who did not respond adequately after 3 previous doses. These findings support the use of a fourth vaccine dose for such patients.

Researchers from University Hospital of Strasbourg studied 92 kidney transplant recipients at 3 independent French university hospitals to investigate whether a fourth dose of an mRNA-based anti–SARS-CoV-2 vaccine would increase antispike IgG titers in kidney transplant recipients who showed a weak serologic response after 3 doses. The patients, who had antispike IgG titers less than 143 BAU/mL 1 month after a third dose of vaccine were given a fourth dose of mRNA vaccine and then measurement of antispike IgG titers were taken 2 to 6 weeks later. The researchers found no safety concerns with the fourth dose and noted that after a median of 29 days, median antispike IgG levels increased significantly, suggesting that a fourth dose of vaccine may be warranted in these patients.