WHO Experts Advise on Ebola Treatments, Vaccines

The World Health Organization (WHO) has convened multiple expert and advisory groups to address the current outbreak of Ebola disease caused by the Bundibugyo virus. This outbreak is occurring in the Democratic Republic of the Congo, with cases also reported in Uganda.

These groups have assessed potential therapeutics and vaccines for the prevention and treatment of Bundibugyo virus disease (BVD). To ensure safe and ethical research, WHO recommends that all identified candidate products be used exclusively within clinical trials.

Prioritizing Treatment and Prevention

Currently, You’ll see no licensed vaccines or therapeutics specifically approved for the prevention and treatment of BVD. However, advisory groups have identified several promising candidates that warrant prioritization for clinical evaluation.

For the treatment of confirmed BVD cases, independent experts recommend prioritizing three candidate therapeutics: the antiviral remdesivir and the monoclonal antibodies MBP134 and Maftivimab®. Evaluation may also include a combination therapy using remdesivir and a monoclonal antibody.

Did You Know? Ervebo is the only licensed Ebola vaccine currently available, but it is approved for the most common Ebola virus in Africa from the Orthoebolavirus family and is not licensed for BVD.

Regarding prevention, the oral antiviral obeldesivir is a priority candidate for post-exposure prophylaxis among contacts of confirmed and probable cases. Experts noted that the success of this approach depends on effective contact tracing, which remains operationally challenging in certain areas of the Democratic Republic of the Congo.

Vaccine Development Timelines

Two primary vaccine candidates are being evaluated for their ability to prevent BVD. The single-dose rVSV Bundibugyo vaccine, developed by the International AIDS Vaccine Initiative (IAVI), is likely to require 7–9 months before it is ready for clinical trials.

Update on the epidemic of Ebola Bundibugyo virus disease in the Democratic Republic of the Congo

Another candidate, ChAdOx1 Bundibugyo, developed by Oxford University and the Serum Institute of India, could potentially become available for efficacy assessment within 2–3 months. This prioritization depends on the acquisition of additional animal data.

For the ChAdOx1 candidate, experts suggest a single-dose approach for contacts of Ebola cases. A two-dose strategy could be considered for high-risk, unexposed populations, such as frontline responders and health-care workers.

Expert Insight: Samantha Carter notes that the reliance on clinical trials for unproven therapeutics highlights a critical tension in outbreak response: the need for immediate intervention versus the necessity of robust, ethical data to ensure patient safety.

Ethical Implementation and Current Response

WHO is working with the governments of Uganda and the Democratic Republic of the Congo, the Africa CDC and the ANRS to implement protocols for clinical field trials. All research must adhere to the highest ethical standards and be conducted in consultation with affected communities.

While these candidates are evaluated, the immediate priority is to stop transmission using established Ebola response tools. These include disease surveillance, rapid testing, contact tracing, isolation, and safe and dignified burials.

These efforts are supported by the WHO R&D Blueprint, which fast-tracks the availability of effective medicines and tests, and SAGE, the principal advisory group for global immunization policies.

Frequently Asked Questions

Are there any approved vaccines for the Bundibugyo virus?
No, there are currently no licensed vaccines specifically approved for the prevention or treatment of BVD.

Can the licensed vaccine Ervebo be used for BVD?
Ervebo is not licensed for BVD, and evidence regarding its cross-protection to other Ebola virus species is inconclusive. WHO recommends it only be used within carefully designed research settings.

What are the prioritized treatments for confirmed BVD cases?
Experts recommend prioritizing the monoclonal antibodies MBP134 and Maftivimab®, as well as the antiviral remdesivir, for evaluation in clinical trials.

How can global health organizations better balance the need for rapid response with the requirements of ethical clinical trials?