Ridgeback Biotherapeutics
Florida biotech that developed Ebanga, the Zaire ebolavirus monoclonal with no approved Bundibugyo efficacy.
Last refreshed: 17 May 2026 · Appears in 1 active topic
Could Ebanga — derived from a Congolese survivor's blood — help in the current Bundibugyo outbreak?
Timeline for Ridgeback Biotherapeutics
No vaccine, no treatment, no MCM
Pandemics and Biosecurity- What is Ebanga and why was it made from a Congolese survivor's blood?
- Ebanga (ansuvimab/mAb114) is an FDA-approved Ebola monoclonal antibody therapy developed at NIAID from antibodies isolated from a Congolese survivor of the 1995 Kikwit Zaire ebolavirus outbreak. NIAID licensed it to Ridgeback Biotherapeutics, which obtained FDA approval in December 2020 after the PALM trial showed it significantly reduced mortality against Zaire ebolavirus.Source: FDA; PALM trial NEJM 2019
- Does Ebanga work against the current Ituri Ebola strain?
- No. Ebanga (mAb114) is approved only for Zaire ebolavirus. The Ituri outbreak is Bundibugyo ebolavirus. No clinical efficacy data for Ebanga against Bundibugyo has been published, and no compassionate-use or cross-reactivity programme has been announced.Source: FDA label; PubMed Central PMC10032372
Background
Ridgeback Biotherapeutics is a privately held Florida-based biotechnology company. It licensed mAb114 (ansuvimab) from NIAID (National Institute of Allergy and Infectious Diseases), where it was originally developed from the blood of a Congolese Ebola survivor. Sold under the brand name Ebanga, it received FDA approval in December 2020 — the second of the two approved Ebola monoclonal therapies to reach the market, the other being Regeneron's Inmazeb. Ridgeback is also the co-developer of molnupiravir, the oral COVID-19 antiviral marketed with Merck.
Ebanga (mAb114) targets the glycoprotein receptor-binding domain of Zaire ebolavirus. Like Inmazeb, it has no licensed indication for Bundibugyo ebolavirus. The PALM trial established both Inmazeb and Ebanga as having significantly lower mortality than ZMapp or remdesivir against Zaire, but the trial was species-specific. No clinical efficacy data for Ebanga against Bundibugyo has been published. The PALM trial results do not provide a basis for cross-species compassionate use without additional data.
The origin of mAb114 carries particular significance in the context of the access-equity debate raised during the Bundibugyo PHEIC: the antibody was derived from the blood of a Congolese survivor of the 1995 Kikwit outbreak, developed at a US government institute using US taxpayer funds, licensed to a US company, and approved as a US-market product whose price and access terms are set by Ridgeback and its distribution partners. The full cost of an Ebanga treatment course runs to tens of thousands of dollars at US hospital prices.