Safety and Immunogenicity of a Third Dose of Mrna‐1273 Vaccine among Cancer Patients

Compared to the general population, cancer patients are at higher risk of morbidity and mortality following SARS‐CoV‐2 infection. The immune response to a two‐dose regimen of mRNA vaccines in cancer patients is generally lower than in immunocompetent individuals. Booster doses may meaningfully augment immune response in this population. We conducted an observational study with the primary objective of determining the immunogenicity of vaccine dose three (100 μg) of mRNA‐1273 among cancer patients and a secondary objective of evaluating safety at 14 and 28 days.