Health Canada authorizes mRNA vaccine trial for Ebola virus causing huge outbreak in Congo

Health Canada has given Moderna the green light to launch a clinical trial for a vaccine targeting the Bundibugyo form of the Ebola virus — which continues to surge throughout the Democratic Republic of the Congo — as experts caution that the outbreak continues to outpace efforts to contain it.

Federal officials announced the recent authorization of Moderna’s mRNA shot on Tuesday, making Canada just the second country to launch a Phase 1 clinical trial for a Bundibugyo vaccine candidate after the U.K.

This form of the virus was long considered rare and has no approved vaccines or treatments, thwarting efforts to clamp down on what is already the second-deadliest Ebola outbreak on record.

More than 1,700 known deaths and 3,800 infections have been recorded since mid-May as health-care teams in remote, conflict-filled areas of Congo are struggling to get the fast-spreading outbreak under control.

Moderna’s trial is being conducted at three sites in Canada — Halifax and Truro in Nova Scotia, and in Toronto — and is expected to enroll roughly 80 participants. The vaccine uses the same mRNA technology that was deployed for the first time during the COVID-19 pandemic.

80 participants expected

In a statement on Tuesday, Health Canada said the clinical trial will assess its vaccine’s safety, determine the right dosing and identify any side-effects in trial participants. 

“Following this, Moderna would be required to conduct additional clinical trial phases before it could seek approval from Health Canada for the vaccine,” it said. 

“Any final submission would need to meet Health Canada’s stringent safety, efficacy and quality standards before the vaccine could be allowed on the Canadian market.”

As part of an agreement with the Coalition for Epidemic Preparedness Innovations (CEPI), a global partnership working to accelerate the development of vaccines, Moderna has agreed to make a minimum of 500,000 doses available to low- and middle-income countries, if the shot is licensed, the company said in a statement.

Moderna’s executive director of global health security and partnerships, Hamilton Bennett, told CBC News that the company hopes to begin analyzing Phase 1 trial results this fall, with the goal of conducting additional trials in impacted communities in Africa after that.

Toronto-based infectious disease specialist Dr. Isaac Bogoch cautioned that any vaccine candidates — such as those in both Canada and the U.K. — could take more than a year to properly study, and may not pan out in time to tackle the current Ebola crisis.

“We know that not all of them are going to work,” he said.

“And it’s important to have several different products being tested simultaneously because, ultimately, we’re going to need this vaccine. The hope is that something’s ready soon enough for this outbreak, but more realistic is that we have something in our back pocket for future outbreaks.”

Bogoch, who has worked in Africa during previous outbreaks, says there is also potential for existing Ebola vaccines — those targeting the Zaire form of the virus — to be used in the current outbreak, as some research suggests they may show some benefit against Bundibugyo as well.

“So if that truly has some cross-protection … it would be far easier to implement because you’ve got a production pipeline, you’ve got safety data, and it’s already been rolled out in in prior outbreaks,” he said.

‘Not under control yet’

Initially confined to the Mongbwalu health zone in Congo’s Ituri province, the current outbreak has expanded to five provinces over the last two months, and is now the largest Ebola outbreak ever reported in Congo, according to the World Health Organization (WHO), which deemed the situation a Public Health Emergency of International Concern back in May.

Neighbouring Uganda has also recorded 20 confirmed Ebola cases and two deaths this year, linked to the situation in Congo, and while the country declared an end to its outbreak on July 28, the WHO said it remains at risk of additional imported Bundibugyo cases.

“The continued increase in cases, expanding geographic spread, and persistently high mortality underscore the rapidly evolving nature of this public health emergency,” the WHO said in its latest update.

Bogoch stressed that health-care workers on the ground have extensive experience tackling Ebola outbreaks over time through infection prevention and control efforts and community outreach, but given the distinct challenges facing teams in Congo right now, it won’t happen overnight.

It took two years to stamp out a 2018 Ebola outbreak in Congo, he explained, “and that was one where a vaccine was available.”

“Sadly, this this is a bit of a trickier one,” Bogoch said. “It’s larger, it’s more complex, and it’s not under control yet.”