AUTHOR=Moreira-Soto Andres , Arguedas Mauricio , Brenes Hebleen , Buján Willem , Corrales-Aguilar Eugenia , Díaz Cecilia , Echeverri Ann , Flores-Díaz Marietta , Gómez Aarón , Hernández Andrés , Herrera María , León Guillermo , Macaya Román , Kühne Arne , Molina-Mora José Arturo , Mora Javier , Sanabria Alfredo , Sánchez Andrés , Sánchez Laura , Segura Álvaro , Segura Eduardo , Solano Daniela , Soto Claudio , Stynoski Jennifer L. , Vargas Mariángela , Villalta Mauren , Reusken Chantal B. E. M. , Drosten Christian , Gutiérrez José María , Alape-Girón Alberto , Drexler Jan Felix TITLE=High Efficacy of Therapeutic Equine Hyperimmune Antibodies Against SARS-CoV-2 Variants of Concern JOURNAL=Frontiers in Medicine VOLUME=8 YEAR=2021 URL=https://www.frontiersin.org/journals/medicine/articles/10.3389/fmed.2021.735853 DOI=10.3389/fmed.2021.735853 ISSN=2296-858X ABSTRACT=

SARS-CoV-2 variants of concern show reduced neutralization by vaccine-induced and therapeutic monoclonal antibodies; therefore, treatment alternatives are needed. We tested therapeutic equine polyclonal antibodies (pAbs) that are being assessed in clinical trials in Costa Rica against five globally circulating variants of concern: alpha, beta, epsilon, gamma and delta, using plaque reduction neutralization assays. We show that equine pAbs efficiently neutralize the variants of concern, with inhibitory concentrations in the range of 0.146–1.078 μg/mL, which correspond to extremely low concentrations when compared to pAbs doses used in clinical trials. Equine pAbs are an effective, broad coverage, low-cost and a scalable COVID-19 treatment.