Experimental vaccines and therapies to combat the deadly Marburg virus will arrive in Rwanda this weekend, where they will be used in clinical trials expected to begin soon, a US government official confirmed Friday.
There are currently no approved vaccines or medications to prevent or treat Marburg, a cousin of the Ebola family of viruses that transmits and causes disease in the same way as Ebola. Although Marburg outbreaks tend to be smaller, the mortality rates of the two infections are comparably high.
Rwanda has never before experienced a Marburg outbreak the matter counts has already reached 41, making it one of the largest ever. Twelve of those people have died. More than 80% of the detected cases are health workers, many of whom were infected at a major health facility in the capital Kigali.
The country has agreed to conduct clinical trials and has signaled its willingness to take swift action.
“We aim to start within days,” Health Minister Sabin Nsanzimana said Thursday at a press conference organized by the Africa Centers for Disease Control and Prevention. “We’re talking about saving health care providers’ lives.”
Nsanzimana sidestepped questions about the design of the trials – in other words, whether multiple vaccines or therapies could be used and compared with each other, or whether they would be compared with a placebo.
It appears that at least two therapeutic options will be available in the country: Gilead Sciences’ antiviral drug remdesivir and Mapp Biopharmaceutical’s experimental monoclonal antibody MBP-091.
Remdesivir has been approved in the United States as a treatment for Covid-19 and has previously been tested as a therapeutic against Ebola. Nsanzimana said Gilead is supplying 5,000 doses of the drug, which is sold commercially as Veklury.
A spokesperson for the Administration for Strategic Preparedness and Response — a division of the Department of Health and Human Services — said the U.S. government is providing vaccine doses and the monoclonal antibody. Both are being developed with the financial support of the Biomedical Advanced Research and Development Authority, or BARDA.
The single-dose vaccine was originally designed by the National Institutes of Health’s Vaccine Research Center and is now being developed by the nonprofit Sabin Vaccine Institute. The institute said it will send 700 doses of the vaccine.
Although several experimental vaccines are in development to protect against Marburg, the Sabin vaccine is believed to be the furthest in the pipeline. The institute is currently conducting a phase 2 trial in Uganda and Kenya.
Nancy Sullivan, director of Boston University’s National Emerging Infectious Diseases Laboratories, led the research to design the vaccine in a previous job at the PRC. She has also played a role in the extensive work that the World Health Organization and its partners have done in recent years to move quickly to test vaccines and medicines for rare diseases like Marburg, when needed.
“I’m pleased that the work that WHO has done has positioned the field to respond to an outbreak,” Sullivan told STAT.
Amy Finan, CEO of the Sabin Vaccine Institute, agreed that the preliminary work here appears to be paying off.
“I think a number of pieces have come together to develop very quickly,” Finan said, noting that because the vaccine is already in a Phase 2 trial elsewhere, the documentation needed to make a new trial is in hand.
Another advantage: the institute had doses of the vaccine that could be used, which is not always the case with an experimental vaccine. IAVI – the International AIDS Vaccine Initiative – is also developing a Marburg vaccine, but is busy manufacturing doses and doesn’t have any to send.
The University of Oxford’s Oxford Vaccine Centre, which designed AstraZeneca’s Covid-19 vaccine, is also developing a Marburg vaccine. STAT reached out to ask about the status of its efforts and whether it has any doses it could supply to Rwanda, but has not yet received a response.
Finan also credited Rwanda for acting quickly in an effort to extinguish this outbreak, which was first confirmed late last week.
“Another hugely important factor that I cannot overstate is the partnership with the Rwandan government,” Finan said. “Rwanda has the healthcare infrastructure to move quite quickly. And I think that really helped us.”