A Potently Neutralizing Antibody Protects Mice against SARS-CoV-2 Infection.

Alsoussi, Wafaa B; Turner, Jackson S; Case, James B; Zhao, Haiyan; Schmitz, Aaron J; Zhou, Julian Q; Chen, Rita E; Lei, Tingting; Rizk, Amena A; McIntire, Katherine M; Winkler, Emma S; Fox, Julie M; Kafai, Natasha M; Thackray, Larissa B; Hassan, Ahmed O; Amanat, Fatima; Krammer, Florian; Watson, Corey T; Kleinstein, Steven H; Fremont, Daved H; Diamond, Michael S; Ellebedy, Ali H

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is responsible for millions of infections and hundreds of thousands of deaths globally. There are no widely available licensed therapeutics against SARS-CoV-2, highlighting an urgent need for effective interventions. The virus enters host cells through binding of a receptor-binding domain within its trimeric spike glycoprotein to human angiotensin-converting enzyme 2. In this article, we describe the generation and characterization of a panel of murine mAbs directed against the receptor-binding domain. One mAb, 2B04, neutralized wild-type SARS-CoV-2 in vitro with remarkable potency (half-maximal inhibitory concentration of <2 ng/ml). In a murine model of SARS-CoV-2 infection, 2B04 protected challenged animals from weight loss, reduced lung viral load, and blocked systemic dissemination. Thus, 2B04 is a promising candidate for an effective antiviral that can be used to prevent SARS-CoV-2 infection.