Ebola researchers in the Democratic Republic of Congo have enrolled more than 250 people in the first clinical trial testing an antiviral pill as post-exposure prophylaxis against the Bundibugyo Ebola virus, as the country's deadliest outbreak on record topped 8,700 confirmed cases, the Associated Press reported this week.
How the EBO-PEP Trial Works
The trial, called EBO-PEP, is testing obeldesivir, an oral antiviral developed by Gilead Sciences that showed effectiveness against several filoviruses — including the Bundibugyo strain — in pre-clinical models. The approach is post-exposure prophylaxis (PEP): participants take the pill soon after suspected exposure, before symptoms appear, to try to stop the disease from developing. It differs from a vaccine, which takes days or weeks to confer protection, and from curative treatment given after illness sets in.
The trial is coordinated by ALIMA (The Alliance for International Medical Action), with participation from DRC's National Institute of Biomedical Research (INRB) in Kinshasa and France's ANRS Emerging Infectious Diseases (Inserm), and is backed by the World Health Organization. PEP centers were set up next to ALIMA-run Ebola treatment units in Bunia and Rwampara, in Ituri province — the outbreak's epicenter. Recruitment began July 14, 2026, with the first participant enrolled on July 16 in Rwampara.
The trial aims to enroll nearly 1,000 adults and children older than 12. To qualify, a person must have had high-risk contact with a confirmed Ebola case — a sick person, a corpse, or a contaminated needle-stick — within the previous five days and show no symptoms. Half the participants receive a placebo; all are examined in person every day for 21 days, with a final follow-up phone call after 42 days. Children under 12 and pregnant or breastfeeding women are covered under a separate compassionate-use protocol using remdesivir.
An Outbreak With No Approved Cure
The urgency is stark: there is no approved vaccine or treatment for the Bundibugyo strain. As of October 6, 2026, DRC had recorded 8,728 confirmed cases and 4,205 deaths — a crude case-fatality rate of 48.2% — across 64 health zones in seven provinces, according to WHO figures via the European CDC. Ituri remains the epicenter with 6,513 cases, including 3,007 deaths.
DRC declared the outbreak in mid-May 2026, and the WHO declared it a public health emergency of international concern on May 17. It is the country's 17th Ebola outbreak since the virus was identified in 1976 — and its largest and deadliest on record. The virus has reached seven provinces, and Kenya confirmed its first imported case on October 6, a Kenyan resident of DRC who traveled through Uganda to Nairobi and died. A linked outbreak in Uganda ended July 28 with 20 cases and 2 deaths.
Why Post-Exposure Prevention Matters
With no vaccine for this strain, breaking the chain of transmission depends on finding exposed people fast — and contact tracing in eastern Congo has struggled to keep pace with the outbreak. A pill that could be given to contacts within days of exposure would be a powerful new tool, if the trial proves it works.
For those enrolling, the motivation is personal. "This disease is killing. It's better to take precautions," one participant who lost a family member to Ebola told the AP. Running the study is itself a challenge: "When a person is emotionally affected, it is not easy to reason with them and ensure they return to the study," said Dr. Jacques Zawadi, an ALIMA investigating physician.
The takeaway: The EBO-PEP trial is the first real test of whether an antiviral pill can stop Ebola after exposure — a potential turning point not just for this outbreak, but for how the world confronts the next one.
Watch: CGTN Africa on the EBO-PEP trial, with more than 250 participants enrolled in DR Congo
Music in this post's reel: Kevin MacLeod - Volatile Reaction (incompetech.com), licensed under CC BY 3.0
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