Covid Antibody Titers in Cancer Patients Following Vaccination with ChAdOx1 nCOV-19 Vaccine

Abstract

Covid-19 has led to significant mortality worldwide, with an increased risk in cancer patients. Vaccination provides significant protection against the infection. The study focuses on the immunogenicity and effectiveness of ChAdOx1 nCoV-19 vaccine in cancer patients within a real-world setting. Blood samples for measuring Covid antibody titers against the receptor binding domain were collected according to a convenient sparse sampling strategy in a real-world setting, with the days of the collection coinciding with their hospital appointment. The antibody titers between different groups were analyzed descriptively. A total of 56 patients were enrolled in the study. There was no apparent effect in antibody titers between patients with solid tumors and hematological malignancies (mean ± standard deviation [SD]: 36.80 ± 41.18 vs. 52.02 ± 26.27), among patients who were undergoing chemotherapy, immunotherapy, or local therapy (mean ± SD: 42.50 ± 44.46 vs. 50.06 ± 51.39 vs. 28.70 ± 25.03), and in patients with up to 90 days and more than 90 days' interval between their last treatment and date of vaccination (mean ± SD: 38.96 ± 42.66 vs. 40.51 ± 38.65). Additionally, there were only 2/56 patients with breakthrough infection, which points out the effectiveness of this vaccine in cancer patients. The ChAdOx1 nCoV-19 vaccine has activity in cancer regardless of the tumor type, type of treatment, or time from the last treatment.