July 14 (Reuters) - Researchers in the Democratic Republic of Congo said on Tuesday they have started enrolling participants in a trial testing Gilead Sciences' GILD.O experimental antiviral obeldesivir as a post-exposure treatment for the ongoing Bundibugyo Ebola outbreak in Congo and Uganda.

Congo's National Institute for Biomedical Research and France's ANRS Emerging Infectious Diseases — with support from humanitarian aid groups, Alliance for International Medical Action (ALIMA) and Medecins Sans Frontieres — are leading the trial in Ituri province, the epicentre of the outbreak, the agencies said in a joint statement.

Here are some details:

• The trial is designed to assess whether post-exposure treatment can reduce the risk of developing Ebola infection after contact with the virus.

• The study aims to enroll about 1,000 people aged 12 years and older, who had high-risk exposure to a confirmed Ebola case within the previous five days but have not developed symptoms.

• Participants will be monitored daily for 21 days, with a final follow-up at 42 days.

• Obeldesivir has shown activity against filoviruses, including the Bundibugyo Ebola virus, in pre-clinical studies.

• The project has received initial funding of 3.4 million euros ($3.87 million) from the Global Health EDCTP3 partnership supported by the European Commission, and $1 million from the Africa Centres for Disease Control and Prevention.

• Africa CDC also helped secure an additional $5 million in funding commitments from South Africa and the Democratic Republic of Congo.

• The study also includes a separate compassionate-use protocol under which Gilead's injectable antiviral remdesivir would be given to children under 12 years and pregnant or breastfeeding women exposed to the virus.

• The outbreak has led to 1,963 confirmed cases in Congo, including 719 deaths, according to government data.

($1 = 0.8777 euros)