Benotmane I, Gautier G, Perrin P, et al. - Researchers assessed antibody responses to a third dose (100 μg) of the mRNA-1273 vaccine (Moderna) in kidney transplant recipients who did not respond to 2 doses of the vaccine. They used the ARCHITECT IgG II Quant test (Abbott) to evaluate anti–receptor-binding domain IgG response following the third vaccine dose. They found a serologic response was elicited by a third dose of mRNA-1273 vaccine in 49% of kidney transplant recipients who did not respond after 2 doses. However, the third dose failed to induce anti–SARS-CoV-2 antibodies development in 51% of the patients, particularly in those under triple immunosuppression. Severe COVID-19 occurrence in some vaccinated transplant recipients may be indicative of a lack of immunity. In the light of these findings, consideration may be given to the use of a third dose of vaccine in organ transplant recipients.