Atoltivimab

Ebola virus (EBOV) remains an important human pathogen within the Ebolavirus genus, having been responsible for at least 17 known outbreaks with an average case fatality rate of 43.92%. Immune therapy using monoclonal antibodies (mAbs) is becoming an increasingly attractive therapeutic method to combat infectious diseases due to its rapid development, low toxicity, and high specificity. The chief surface target of EBOV particles is the GP glycoprotein, which also appears on the surface of EBOV-infected cells, offering opportunities for both neutralizing and cytotoxic (i.e. through Fc-mediated immune effector function) antibody effects to play a role in combatting EBOV infection. A recent large-scale study elucidated that both neutralizing and Fc-mediated functions of antibodies were important for therapeutic benefit in animal models of EBOV infection. INMAZEB™, formerly referred to as REGN-EB3, combines the three humanized IgG1κ mAbs Atoltivimab (REGN 3470), Odesivimab (REGN 3471), and Maftivimab (REGN 3479) in equimolar proportions. All three mAbs bind to a distinct portion of the GP glycoprotein and collectively provide neutralizing and Fc-mediated immune effector function against EBOV in vitro and protection against EBOV infection in vivo. INMAZEB™ is produced by Regeneron Pharmaceuticals and was granted FDA approval on October 14, 2020.

Atoltivimab is indicated in combination with Odesivimab and Maftivimab for the treatment of Zaire ebolavirus infection in adult and pediatric patients, including neonates born to a mother who has been confirmed positive by RT-PCR for Zaire ebolavirus infection. This combination has not been established as efficacious for any other species within either the Ebolavirus or Marburgvirus genera; special care should be taken to evaluate the susceptibility of circulating Zaire ebolavirus strains before beginning treatment, and the possible emergence of resistance should be monitored.

• Ebola Virus Disease