The approval, which was based on the PALM randomized controlled trial, is the first FDA-approved treatment for Ebola virus infection.
The FDA has approved a monoclonal antibody mixture (Inmazeb; Regeneron) for the treatment of Zaire ebolavirus (Ebola virus) infection in adult and pediatric patients.
The drug mixture is composed of atoltivimab, maftivimab, and odesivimab-ebgn and targets and blocks the glycoprotein on the surface of the Ebola virus that attaches to the cell receptor, fuses the viral and host cell membranes, and allows the virus to enter the cell.
“Today’s action demonstrates the FDA’s ongoing commitment to responding to public health threats—both domestically and abroad—on the basis of science and data,” said FDA Commissioner Stephen M. Hahn, MD. “This approval was made possible because of our steadfast dedication to facilitate the development of safe and effective treatments for infectious diseases as part of our vital public health mission.”
Ebola virus is 1 of 4 Ebolavirus species that have the potential to fatally infect humans through direct contact with blood, body fluids, and tissues of infected individuals and wild animals, as well as with contaminated surfaces and materials, such as bedding and clothing.
The agency’s approval was based on data provided by the PALM trial, which incorporated 382 adult and pediatric patients with confirmed Ebola virus infection in the Democratic Republic of Congo (DRC) amid an outbreak that took place in 2018 and 2019.
Led by the US National Institutes of Health and the DRC’s Institut National de Recherche Biomédicale, the multi-center, open-label, randomized controlled trial (RCT) administered 50 mg of each monoclonal antibody intravenously (IV) to 154 patients; another 168 patients received an investigational control. The primary efficacy end point was 28-day mortality.
Of the 154 patients who received the monoclonal antibody combination, 33.8% died after 28 days, compared with 51% of the patients receiving the investigational control. In the expanded access program, another 228 individuals received the drug combination.
The first vaccine for the prevention of Ebola virus was approved by the FDA in December of 2019 based on a study conducted in Guinea amid the outbreak that took place from 2014 to 2016. Patients who receive the most recently approved drug combination for Ebola virus should avoid the concurrent administration of a live vaccine, as the treatment has the potential to reduce the vaccine’s efficacy, according to the FDA.
The most common symptoms of the antibody combination include fever, chills, tachycardia, tachypnea, and vomiting, although these adverse events (AEs) are also themselves symptoms of Ebola virus infection.
“Today’s approval highlights the importance of international collaboration in the fight against Ebola virus,” said John Farley, MD, MPH, director of the Office of Infectious Diseases in the FDA’s Center for Drug Evaluation and Research. “The urgent need for advanced therapies to combat this infectious disease is clear, and today’s action is a significant step forward in that effort.”