More than 250 people have enrolled in a clinical trial testing a drug designed to prevent Ebola infection in Congo, a potentially crucial step as health authorities struggle to contain the country’s deadliest outbreak of the disease.
The drug targets Bundibugyo virus, the strain driving the fast-moving outbreak. There is currently no approved vaccine or treatment for the virus, making the trial one of several studies launched to find new ways to protect people exposed to the disease and slow its spread.
The trial began in July at a health center in eastern Congo’s Ituri province, the epicenter of the outbreak.
The Associated Press (AP) spoke this week with participants and doctors involved in the study. Those enrolled include people who have been exposed to the virus, including health workers and relatives of patients.
At least 8,300 confirmed cases and 4,000 deaths have been recorded since the outbreak was declared in mid-May in eastern Congo, according to authorities. The virus has spread to seven provinces and continues to outpace efforts to identify cases, trace contacts and contain transmission.
The trial is testing Gilead's experimental antiviral pill, called obeldesivir, which is given soon after suspected contact with the virus to prevent the disease from developing. That approach is called post-exposure prophylaxis, or PEP.
One participant in the trial known as EBO-PEP told AP that she enrolled in the study in August after her husband tested positive for Ebola. She says so far no one from her family developed symptoms.
She and other trial participants requested anonymity to protect their privacy due to the sensitive nature of the Ebola outbreak and the medical protocol involved.
Ebola disease only spreads once symptoms begin. People exposed to infected patients have to wait to see if they get sick. Finding people at high risk of incubating the Bundibugyo virus - also known as contact tracing - has proved difficult in Congo.
Another participant said two of their family members had caught Ebola, and one of them had died. "This disease is killing. It’s better to take precautions,” he said.
The trial, coordinated by ALIMA, a medical nonprofit, aims to recruit nearly 1,000 adults or children over the age of 12 who have come into contact with a confirmed case within the last five days but have no symptoms. Half will get a placebo.
Participants are monitored in person every day for 21 days, with a final phone call after 42 days, according to Dr. Godefroid Basara, who is working on the trial.
ALIMA said that if trial participants begin to develop symptoms, they will immediately receive supportive treatment, which has been shown to be helpful when symptoms are caught early.
If the pill proves effective, it could help break the infection chain.
"It differs from a vaccine, which may take days or weeks to provide protection. It is also different from curative treatment because it is intended for people who are not yet showing symptoms,” ALIMA research coordinator Dr. Guilavogui Jean Paul Yassa said.
Dr. Jacques Zawadi, an investigating physician working with ALIMA at the trial center, said most participants are happy to take part in the study, but it had been challenging encouraging some people who live far from the center to sign up.
He said the study is sometimes disrupted when participants find out their family members have died from the disease.
"This is the biggest challenge we face. When a person is emotionally affected, it is not easy to reason with them and ensure they return to the study,” he said.
The trial partners also include Congo’s National Institute of Biomedical Research and the French institute ANRS Emerging Infectious Diseases.
As new vaccines are under development elsewhere, Congo started vaccinating health workers with the Ervebo vaccine which was effective during previous Ebola outbreaks caused by a different, more common virus. Authorities have said Ervebo could offer some protection against Bundibugyo, but whether the vaccine can actually prevent illness is still being studied.
On Thursday, humanitarian organization Doctors Without Borders said a staff member had tested positive for Ebola and was being evacuated to the Netherlands. In June, a humanitarian physician with ALIMA also tested positive after returning to France from one of the virus hot spots.
The World Health Organization has said the outbreak continues to outpace efforts to track and slow the spread, and is set to exceed West Africa’s regional outbreak between 2014 and 2016 - the deadliest on record - which killed 11,000 people.
