Efficacy and safety of BNT162b2 mRNA vaccine in a cohort of 90 transfusion dependent thalassemia patients

Thalassemia is one of the most common genetic disorders. Data from an international registry show that thalassemia is associated with a reduced risk of in-hospital complications and mortality due to SARSCoV-2 infection; however, a recent study showed that patients with hemoglobinopathies exhibit an increase in age-standardised lethality. Ghoti et al. recently describes a cohort of 105 patients who exhibited a high susceptibility to SARS-CoV-2 infection mainly asymptomatic or with mild disease. However the efficacy of vaccines against SARSCoV- 2 in this patient population is not yet defined. In our previous work we proposed anti-COVID 19 vaccination with BNT162b2 (Comirnaty) to a cohort of transfusion-dependent thalassemia (TDT) patients and we demonstrated that TDT patients are good responders to Comirnaty in terms of clinical outcomes and humoral response. Other studies also confirmed that mRNA vaccines appear to be effective in inducing protective immunogenic response in TDT patients. Overall, in these studies5–7 there are no data of follow-up post vaccination in TDT patients. The aim of our work was to evaluate the efficacy and safety of BNT162b2 mRNA vaccine and follow up for SARS-CoV-2 infection in a cohort of 90 TDT patients.