The World Health Organization has announced the start of the first clinical trial of an Ebola vaccine during the outbreak in the Democratic Republic of Congo. WHO director-general Tedros Adhanom Ghebreyesus said in a social media post on Friday that trial participants had received the Ervebo vaccine in Bunia, the capital of the northeastern Ituri province.
Ituri is the hotspot at the centre of the epidemic, according to the WHO chief. He said the trial would help establish whether any vaccine candidates designed for the Bundibugyo virus are effective, and described the effort as one led by the DRC with WHO support.
Ervebo to be tested against the Bundibugyo species
Ervebo is approved for use against the more common Zaire strain of Ebola. It will now undergo a full-scale human trial to see whether it offers any cross-protection against Bundibugyo, the species behind the current epidemic.
The trial is built on what the source calls a single framework, known as Tumaini, that can assess the safety, efficacy and immunogenicity of several vaccines at once. It will use ring vaccination, meaning it targets contacts judged to be at high risk of infection.
Candidate vaccines and who will be included
Two Bundibugyo-specific candidates are set to join the trial. Both are currently moving through smaller, earlier-stage clinical studies. One is a ChAdOx1 adenoviral vector vaccine developed by the University of Oxford, while the other, from the US-based Moderna group, uses mRNA technology.
The Coalition for Epidemic Preparedness Innovations, which funds both candidates, said in a statement that they are expected to enter the trial shortly. The study will also include pregnant women and children aged 12 years and older, groups that are often excluded from clinical trials. WHO emergencies director Chikwe Ihekweazu said the trial was designed to produce the rigorous evidence needed to determine whether the vaccines could protect people at risk.
Scale of the outbreak across Africa
The DRC declared its 17th outbreak in May, which is also its worst on record. Since then, it has reported more than 9,700 cases, with deaths exceeding 4,600. In response, the WHO triggered a public health emergency of international concern, its second-highest alert level.
The outbreak has now been reported in four countries across eastern, central and western Africa. This gives it the widest geographic spread of any Ebola outbreak on the continent so far.
