REGEN-COV antibody combination in patients with lymphoproliferative malignancies and SARS-CoV-2 infection.

Patients with lymphoproliferative diseases are at high risk for SARS-CoV-2-related complications and mortality. The role of casirivimab and imdevimab (REGEN-COV), a neutralizing antibody cocktail, to treat immunocompromised hemato-oncological patients with SARS-CoV-2 disease 2019 (Covid-19) remains unknown. Here, we present our clinical experience on the outcome of 15 hematological patients treated with REGEN-COV for SARS-CoV-2 infection. Most patients failed to respond or achieved low antibody titer after 2-3 doses of BNT162b2 mRNA vaccine. All patients experienced clinical improvement with no mortality within a median follow-up of 70 days. In conclusion, early administration of REGEN-COV to high-risk hematological patients may prevent clinical deterioration and mortality from SARS-CoV-2 infection. The effectiveness of neutralizing antibodies may vary depending on the virus variants and in particular with the omicron variant (B.1.1.529).