摘要 : Patients with cancer are at increased risk of severe COVID-19 disease because of immunosuppression caused by the cancer and/or cancer treatments (Ehmsen et al., 2021b; Tian et al., 2020). We and others have characterized the anti-... 展开 Patients with cancer are at increased risk of severe COVID-19 disease because of immunosuppression caused by the cancer and/or cancer treatments (Ehmsen et al., 2021b; Tian et al., 2020). We and others have characterized the anti-SARS-CoV-2 immune response after two and three COVID-19 mRNA vaccinations in patients with solid and hematologic cancers and observed insufficient responses in a substantial portion following the second vaccination ((Ehmsen et al., 2021a; Gounant et al., 2022; Herishanu et al., 2022) but an improved response following the third vaccination (Ehmsen et al., 2022). We further showed that the anti-SARS-CoV-2 spike receptor binding domain (anti-S) IgG antibody titers declined rapidly within the first 3 months after both the second and third vaccination. This, in combination with high infectivity rate of COVID-19 in the population in the winter of 2021-2022, made the Health Authorities in several countries, including Denmark, recommend a fourth mRNA COVID-19 vaccination to boost the immune response in this patient group. Here, we assess alterations in antibody titers (anti-S IgG) in blood samples following a fourth mRNA vaccination from patients with solid and hematologic malignancies, and we assess the waning antibody response at 3 months following the fourth vaccination. 收起