Longevity of the humoral and cellular responses after SARS-CoV-2 booster vaccinations in immunocompromised patients

We assessed the humoral and cellular immune responses after two booster mRNA vaccine administrations [BNT162b2 (Pfizer-BioNTech vaccine)] in cohorts of immunocompromised patients ( n = 199) and healthy controls (HC) ( n = 54). All patients living with HIV (PLWH) and chronic kidney disease (CKD) patients and almost all (98.2%) of the primary immunodeficiency (PID) patients had measurable antibodies 3 and 6 months after administration of the third and fourth vaccine dose, comparable to the HCs. In contrast, only 53.3% and 83.3% of the multiple sclerosis (MS) and rheumatologic patients, respectively, developed a humoral immune response. Cellular immune response was observed in all PLWH after administration of four vaccine doses. In addition, cellular immune response was positive in 89.6%, 97.8%, 73.3% and 96.9% of the PID, MS, rheumatologic and CKD patients, respectively. Unlike the other groups, only the MS patients had a significantly higher cellular immune response compared to the HC group. Administration of additional vaccine doses results in retained or increased humoral and cellular immune response in patients with acquired or inherited immune disorders.