Impact of SARS-CoV-2 vaccination and monoclonal antibodies on outcome post CD19-CAR-T: an EPICOVIDEHA survey.

Patients with previous CD19 directed chimeric antigen receptor T cell therapy (CAR T)-cell therapy have a prolonged vulnerability to viral infections. Coronavirus diseases 2019 (COVID-19) has a great impact and has previously been shown to cause high mortality in this population. Until now, real world data of the impact of vaccination and treatment on patients with COVID-19 after CD19 directed CAR T-cell therapy are lacking. Therefore, this multicenter retrospective study was conducted with data from the EPICOVIDEHA survey. Sixty-four patients were identified. The overall mortality caused by COVID-19 was 31%. Patients infected with the Omicron variant had a significantly lower risk of death due to COVID-19 compared to patients infected with previous variants (7% versus 58% (P=0.012)). Twenty-six patients were vaccinated at time of COVID-19 diagnosis. Two vaccinations showed marked but unsignificant reduction risk of COVID-19 caused mortality (33.3% versus 14.2% (P=0.379)).Also the course of disease appears milder with less frequent ICU admissions (39% versus 14% (P=0.054)) and shorter duration of hospitalization (7 versus 27.5 days (P=0.022)). Of the available treatment options, only monoclonal antibodies seemed to be effectively reducing mortality from 32% to zero (P=0.036). We conclude that survival rates of CAR T-cell recipients with COVID-19 improved over time and that the combination of prior vaccination and monoclonal antibody treatment significantly reduces their risk of death.