EARLY TREATMENT WITH BAMLANIVIMAB ALONE DOES NOT PREVENT COVID-19 HOSPITALIZATION AND ITS POST-ACUTE SEQUELAE. A REAL EXPERIENCE IN UMBRIA, ITALY.

Background and Objective The use of monoclonal antibodies to the SARS-Cov-2 spike protein for early treatment of COVID-19 disease is being evaluated, with only phase 2 studies available, to date. Emergency authorization of bamlanivimab monotherapy was get in November 2020 by the FDA and in March 2021 by italian agency AIFA. Its use was then revoked in April 2021 by both. This study reports the results of bamlanivimab utilization in monotherapy in Umbria (Italian region), in order to verify whether, in a population with multiple risk factors, comparable results to phase 2 BLAZE1 trial had been obtained. Methods Retrospective observational study, between March and April 2021, in patients treated with bamlanivimab was performed. Demographic and clinical characteristics before and after infusion were evaluated.  Moreover, a telephone interview about 30 days after the infusion was carried out to evaluate the overall course. Results All  patients had an early infection (mean 4±1.73 days), almost all by alpha variant (97%). No adverse events to treatment were observed. Altogether within 30 days, the hospitalization rate was 20%, 15% for  COVID-19 related pathologies , versus  4% at 11 days  in  BLAZE1 phase 2 study.  Worsening of some symptoms observed at baseline such as asthenia (77 vs 51.3%), shortness of breath (38 vs 23%) was registered, as well as  the onset of non-restorative sleep (41%). Conclusions The clinical outcome after bamlanivimab monotherapy was far below the expectation despite the patients had been infected by a theoretically sensitive viral variant.