Outcome of COVID-19 patients with haematological malignancies after the introduction of vaccination and monoclonal antibodies: results from the HM-COV 2.0 study

Purpose: . Patients with hematological malignancies (HM) and SARS-CoV-2 infection present a higher risk of severe COVID-19 and mortality. The aim of the study was to investigate whether vaccination and monoclonal antibodies (mAbs) have modified the outcomes of HM patients with COVID-19. Methods: . Single-center retrospective study in HM patients hospitalized due to SARS-CoV-2 infection from March 2020 to April 2022. Patients were divided into PRE-V-mAb group (patients hospitalized before the introduction of vaccination and mAbs) and POST-V-mAb group (patients hospitalized after the use of vaccine and mAbs). Results: . A total of 126 patients were included (65 PRE-V-mAb and 61 POST-V-mAb). POST-V-mAb patients showed a significantly lower risk of Intensive Care Unit (ICU) admission (8.2% vs 27.7%, p=0.005), shorter viral shedding [17 (IQR 10-28) vs 24 days (IQR 15-50), p=0.011] and shorter hospitalization length [13 (IQR 7-23) vs 20 (IQR 14-41) days, p=0.0003] compared to the PRE-V-mAb group. Nevertheless, both in-hospital and 30-day mortality rates did not significantly differ between the two groups (29.5% POST-V-mAb vs 36.9% PRE-V-mAb and 21.3% POST-V-mAb vs 29.2% PRE-V-mAb, respectively). At the multivariable analysis an active malignancy (p=0.042), a critical COVID-19 at admission (p=0.025) and the need for high-level of oxygen support at respiratory worsening [either HFNC/CPAP (p=0.022) or Mechanical Ventilation (p=0.011)] were independently associated with in-hospital mortality. In the subgroup of POST-V-mAb patients, receiving therapy with mAbs was a protective factor (p=0.033). Conclusion: . Despite the new therapeutic and preventive strategies available, HM patients with COVID-19 disease represent an extremely vulnerable group with still high mortality rates.