Congo starts Bundibugyo Ebola vaccine trial in Bunia

The first participant in a large vaccine trial against the Bundibugyo strain of Ebola was vaccinated Friday, October 23, in Bunia in eastern Congo. Bundibugyo is the strain behind the deadliest outbreak the country has ever recorded. The Phase 2/3 study is called Tumaini, which means "hope" in Swahili, and its first vaccine is Merck & Co.'s ↗ 0.80% Ervebo. Ervebo is licensed against a different Ebola species, and no one yet knows whether it protects people against Bundibugyo, according to CEPI, the epidemic-preparedness group funding the study. Two shots designed specifically for Bundibugyo could join the trial within weeks, Bloomberg reported. One comes from Moderna ↗ 4.10% and the other from the University of Oxford and the Serum Institute of India.bloomberg.com+1

No vaccine or specific treatment has been approved for Bundibugyo virus disease, the World Health Organization said. As of October 20, Congo had recorded 9,704 confirmed cases and 4,687 deaths across 66 health zones in eight provinces, a case fatality rate of 48.3%.who.int

How the trial works

Researchers can test several vaccine candidates side by side under one protocol in Tumaini. They use ring vaccination, which means vaccinating the contacts of confirmed patients, who face the highest risk of infection, CEPI said. Congo's Institut National de Recherche Biomédicale and the University of Antwerp lead the study, and the health ministry oversees it. Partners include the WHO, Africa CDC and Médecins Sans Frontières. Pregnant women and children aged 12 and older can take part, and children as young as one can receive Ervebo.cepi.net

"This is much more than a research study," said Chikwe Ihekweazu, who heads the WHO's Health Emergencies Programme. "If successful, this would be the first time we have clear evidence of vaccine efficacy against Bundibugyo virus," he said in the CEPI statement. CEPI chief executive Richard Hatchett said the absence of a vaccine "is being counted in the DRC every day, in lives lost."cepi.net

A widening outbreak

Congo declared the outbreak on May 15. Within days, the WHO named it a public health emergency of international concern, and it is now the second-largest Ebola outbreak on record, CEPI noted. It is also spreading beyond Congo. Kenya had reported nine cases and one death as of October 20, and Nigeria confirmed an imported case in Abuja that same day in a patient who had traveled from Uganda, the WHO said.who.int+1

Before the trial began, Congo had already started giving Ervebo to frontline workers. In August, international stockpile managers released 70,000 doses: 50,000 for health workers and 20,000 for a clinical trial, according to the WHO. Early lab and animal data suggest the shot may offer some cross-protection, but WHO immunization advisers concluded the evidence was too weak to support routine use against Bundibugyo, the agency said. Tumaini is meant to answer that question.who.int+1