The FDA announced Wednesday that it has approved Regeneron Pharmaceuticals’ triple antibody cocktail Inmazeb (atoltivimab/maftivimab/odesivimab-ebgn) for use in adult and paediatric patients, making it the first drug cleared in the US to treat Ebola virus infection. According to the agency, the three monoclonal antibodies that make up Inmazeb bind to different, non-overlapping epitopes on the Zaire ebolavirus glycoprotein, blocking its ability to attach and enter into host cells.
“Decades of investment in our VelociSuite rapid response technologies…together with remarkable cooperation between leading international health organisations and governments, have led to this important moment,” commented George Yancopoulos, chief scientific officer at Regeneron. He noted that the company has “[applied] the same sophisticated technologies and manufacturing capabilities against COVID-19,” notably with its experimental dual antibody treatment REGN-COV2.
Cut Ebola deaths more than ZMapp, Veklury
The FDA evaluated Inmazeb, also known as REGN-EB3, under a priority review. The application was supported by data from the 681-patient PALM trial, which last year was stopped early after an interim analysis showed that when it came to reducing mortality from Ebola virus disease, Inmazeb was superior to Mapp Biopharmaceuticals’ ZMapp, as well as Gilead Sciences’ antiviral agent Veklury (remdesivir), which is itself now at the forefront as a treatment in the fight against COVID-19.
Meanwhile, detailed PALM results later published in the NEJM, found Inmazeb to be superior to ZMapp across multiple measures. On the primary endpoint of 28-day mortality, death occurred in 33.5% of patients given Inmazeb, compared with 51.3% for ZMapp, while Regeneron’s treatment also bested ZMapp on the secondary goal, which looked at reduction in the number of days until the Ebola virus was no longer detected in the bloodstream. Regeneron’s therapy is administered as a single, weight-based intravenous infusion.
Inmazeb, which has received orphan drug and breakthrough therapy designations from the FDA, is being developed under an ongoing collaboration with the US Biomedical Advanced Research and Development Authority (BARDA). Regeneron stated that “with BARDA support, we continue to provide Inmazeb for free in response to outbreaks in the Democratic Republic of the Congo,” and the company is also “actively working with non-governmental organisations and public health agencies to ensure continued access to Inmazeb in low- and middle-income countries.”