Peer-reviewed article
Post-exposure prophylaxis with a monoclonal antibody cocktail after Bundibugyo ebolavirus exposure in adults and children.
Gaebler C, Le HN, Martin L, Tarnow P, Gratopp A et al. ·
Summary
Written by AI, not yet AICS's view · claude-haiku-4-5-20251001Five family members, including four unvaccinated children aged 1-7 years, received an investigational monoclonal antibody cocktail (MBP134) as emergency post-exposure prophylaxis after exposure to Bundibugyo ebolavirus. The treatment was well tolerated with no adverse events, and all recipients remained free of clinical or laboratory evidence of infection during the 21-day monitoring period. The antibodies persisted and showed neutralizing activity against multiple ebolavirus species, supporting further evaluation of this treatment for protecting high-risk contacts during outbreaks.
Key points
- All five recipients, including four children aged 1-7 years, remained free of clinical or laboratory evidence of Bundibugyo virus disease throughout 21-day monitoring
- MBP134 administration was well tolerated with no treatment-related adverse events reported
- Plasma antibodies persisted throughout follow-up and mediated broad neutralizing activity against multiple Orthoebolavirus species
- The vaccinated adult developed endogenous BDBV-reactive IgM and IgA antibodies despite persistently negative PCR results
- This represents the first human evaluation of MBP134 as post-exposure prophylaxis for Bundibugyo ebolavirus
Limitations
This is a case report of five individuals from a single family cluster with no control group, making it impossible to determine whether the absence of infection was due to the treatment or natural infection rates after exposure. The small sample size and short 21-day follow-up period are insufficient to establish efficacy or longer-term safety.
Abstract
Five individuals from a single family cluster-one rVSV-ZEBOV-vaccinated adult and four unvaccinated children aged 1-7 years-received investigational MBP134 as post-exposure prophylaxis (PEP) 5-6 days after high- to intermediate-risk occupational or household exposure to Bundibugyo ebolavirus (BDBV). MBP134 is a broadly neutralizing monoclonal antibody cocktail that has conferred protection against BDBV in non-human primates but, to our knowledge, has not previously been evaluated as PEP in humans. Given the absence of approved preventive interventions against BDBV and the substantial case-fatality rate of Bundibugyo virus disease (BVD), MBP134 was administered as an individual treatment attempt under emergency Investigational New Drug (eIND) authorizations. Administration was well tolerated, with no treatment-related adverse events. Throughout the 21-day monitoring period, all family members remained free of clinical or laboratory evidence of BVD, as assessed by daily medical evaluation and serial polymerase chain reaction (PCR) testing. Plasma Orthoebolavirus-reactive antibodies were detected after infusion, persisted throughout follow-up and mediated broad neutralizing activity against multiple Orthoebolavirus species, including authentic BDBV. Notably, endogenous BDBV-reactive IgM and IgA were detected in the adult after high-risk exposure despite persistently negative PCR results. Together, these findings support prospective evaluation of MBP134 as PEP for high-risk adult and pediatric contacts during BDBV outbreaks.