Efficacy (and safety) of vaccination against SARS-CoV-2 in cancer patients on active treatment

Since the COVID-19 pandemic, cancer patients have been recognized as a group with an increased risk of complications, if they become infected with the SARS-CoV-2 virus. However, they were not included in registrational trials for COVID-19 vaccines. In the last few months data from studies investigating the efficacy and safety of COVID-19 vaccines in cancer patients receiving systemic treatment have become available. It has been established that the efficacy (regarding humoral and cellular response) and safety of COVID-19 vaccines in solid cancer patients are comparable to that in healthy individuals. On the other side, humoral response is very low or even undeterminable in haematological patients, especially in those receiving anti- CD 20+ targeted therapy or Bruton kinase inhibitors. However, a cellular response is preserved and vaccination, including with a third dose, is reasonable. Cancer patients who were infected with SARS-CoV-2 and then vaccinated developed much better humoral response.