West African Scientists Are Leading the Science Behind a Malaria Vaccine
Researchers in Mali have been working for decades on the treatment that’s now in the final phase of clinical trials
This spring, researchers reported that a vaccine for malaria showed promise and entered a critical phase of testing. The Lancet study described how the R21/Matrix-M vaccine appears to be over 75 percent effective in preventing malaria, a mosquito-borne infectious disease that claims more than 400,000 lives every year. Nine out of 10 malaria victims live in Africa, most of them children under the age of five.
Almost invisible in the media reports are key contributors to that research: malaria scientists born, raised and now working in some of the world’s poorest countries in Africa.
For much of the 20th century, infectious disease research was led by agencies in industrialized countries. Malaria was endemic in the southeastern United States until state-level campaigns and mosquito-control efforts brought incidences down in the late 1940s. Successful vaccination campaigns in Europe and the U.S.—including the first polio vaccine in the early 1950s—fueled the notion that global collaboration could eradicate a disease from the planet. Industrialized medical research and vaccine development extended its reach to developing countries, but were conducted primarily by Western scientists. The malaria vaccine, however, represents the fruit of years of work by African scientists combatting a disease that is devastating African communities.
In Mali, researchers at the Malaria Research and Training Center (MRTC) in Bamako, the nation’s capital, have been striking hard at the roots of malaria, leading toward this vaccine moment.
Created 30 years ago with international support from universities and the World Health Organization, MRTC has become a hub for a range of clinical studies. The center’s co-founder and long-time director, Ogobara “Ogo” Doumbo, grew up the grandson of traditional healers in a small village 600 miles northeast of the capital. He studied medicine at the University of Bamako, and started practicing in 1981. When he grasped the scale of malaria’s cost among his patients, he realized he could have greater impact by enlisting more young doctors and studying deeply in the fields of parasitology and tropical medicine. He earned a PhD in parasitology from the University of Montpelier in France. Returning to Mali, he created a formidable pool of researchers, with several involved in the new R21 vaccine, leading the vaccine work in Mali and conducting trials.
“We’ve been continuing to do what he taught us to do, which is do good science,” says Abdoulaye Djimdé, director of parasitology research at MRTC. “We’ve been fighting for grants, winning large grants, and continuing to do vaccine research.”
The first vaccinations in the next phase of R21 vaccine testing—phase 3 trials—have already begun in Mali, says Djimdé, who has led the center’s research on the malaria parasite since Doumbo’s death in 2018. The phase 3 trial will gauge the vaccine’s safety and effectiveness in 4,800 children up to 3 years old in Mali, Burkina Faso, Kenya and Tanzania, testing the vaccine in areas representing different patterns of malaria seasonality and transmission.
Djimdé feels keenly the responsibility for the vaccine’s progress. “We are always nervous when a vaccine reaches this phase,” he admits.
That’s because so much is at stake. This research is not simply a matter of professional prestige for these researchers, he explains. “Living in the communities, suffering from the disease, and having our children and our siblings suffering from the disease—it gives you a fresh look at the problem,” Djimdé says. “We are here to solve problems that our people and we ourselves suffer from.”
Djimdé gives credit to Doumbo for the group’s focus and high standards. Doumbo communicated the goal vividly, comparing malaria’s impact to that of several tsunamis hitting African children every year.
Malaria’s symptoms are brutal—high fever, headaches, vomiting, diarrhea and night sweats—and the effects can be long-lasting, akin to “long-Covid” experienced by some Covid-19 patients, where symptoms continue long after the infection. Furthermore, malaria’s toll is measured not solely in health effects, as devastating as those are. Endemic malaria also wreaks chaos on family finances shredded by medical fees, lost productivity and potential.
“Africa has lost a lot of Einsteins, a lot of Pasteurs, a lot of Bill Gateses because of malaria,” Doumbo told me in a 2011 interview. Countries across Africa where malaria is endemic—including Benin, Burkina Faso, Mali, Mauritania, Senegal—are among the world’s 46 “least developed countries” according to United Nations statistics. Beyond improving public health, Doumbo believed, eliminating the disease would open up African capacity for innovation and creative solutions.
Investment in malaria control in recent decades has reaped significant returns. According to the World Health Organization (WHO), innovations such as rapid testing and improved treatment have prevented 7.6 million malaria deaths. However, progress was also made more daunting by the coronavirus pandemic. Covid-19, with some similar symptoms, complicated the diagnosis and delayed treatment of many malaria patients, and travel restrictions limited the reach of health workers fighting the disease.
Doumbo was among the first African researchers to lead an international malaria vaccine trial. Louis Miller, who visited Mali in 1988 as then-head of malaria research for the National Institutes of Health (NIH), recalls that the mostly white U.S. Army medical team at Walter Reed grossly underestimated the African scientists, saying they would need at least five years of training in the experimental methods. “They didn’t know what a brain Ogo was!” says Miller, still a researcher with NIH at age 86. “I said to them, ‘You can’t go there without working closely with Ogo,’” Miller adds. “He always wanted to do it all. So he took this on and did it, and satisfied a very critical group from Walter Reed.” Within a year or so, Doumbo’s team was ably managing the trial.
Djimdé, like Doumbo, hails from Mali’s remote Dogon region. He was 7 or 8 years old when he first met his mentor. “He was really inspirational for us young minds,” says Djimdé. “He played a big role in us trying to become like him and to thrive in school.”
Having put himself through the University of Bamako’s pharmacology doctorate program, Djimdé started at MRTC in 1993, volunteering every afternoon after working at a pharmacy. Doumbo rewarded his dedication with a chance to attend training at NIH. Djimdé then received his medical degree from the University of Maryland.
Doumbo used global opportunities and incentives to foster home-grown research talent. To retain good researchers at MRTC, he stayed in touch with them during their overseas fellowships, provided incentives for their return with the prospect of meaningful research, and delegated authority.
Harold Varmus, a Nobel Prize winner for the discovery of the cellular origin of cancer-causing genes from retroviruses and now senior advisor to the dean and provost at Weill Cornell Medicine, visited Mali in 1997, when he was NIH director. He traveled with Miller and Doumbo. He, too, was struck by Doumbo’s dedication. “His determination, deep knowledge of malaria, and positive effects on coworkers and government leaders were quickly evident, even in a short visit,” Varmus said by email a decade ago. “One of the great things about his effort was his engagement” with communities, which conveyed to the public the causes of malaria transmission and prompted construction of clinics and wells for clean drinking water.
Networking among African scientists diversified their collaborations beyond the postcolonial connections that often remained between African and northern institutions. This led to groups such as the Pan-African Mosquito Control Association, a dynamic professional society with chapters across the continent.
When Doumbo died suddenly in 2018 after a brief illness, that nurturing environment was at risk. “Many people were worried that things might fall apart after he passed away,” Djimdé says. “But we were conscious of that as a team, as a group. We wanted to prove people wrong.” They kept the program together and, in a peer election, selected Djimdé to lead the group.
The researchers at MRTC have continued winning major international grants, moving into drug discovery, vaccine discovery and the biology of malaria transmission. In addition to the applied research that made its reputation, Djimdé says, MRTC is expanding towards basic research. (Applied research is focused on finding workable solutions for known problems, while basic research is a quest for knowledge itself—and may or may not have direct application.)
That growth is a testament to Doumbo. “The main legacy is really the people he trained, the infrastructure he helped to build, and the research environment he helped to create,” Djimdé says. “Everybody talks about sustainability. That's an example of sustainability where you've created something that outlives yourself. And the R21 [vaccine] is just one example.”
Another malaria vaccine, Sanaria PfSPZ, developed with the Maryland-based firm Sanaria, is also showing successful prevention rates in clinical trials, including some at the Mali team’s sites.
But over time, some observers wondered if the donor funding showered on international research actually benefited public health in those countries. After all, clinics continue to struggle to provide even basic care.
Yacine Diop Djibo, who leads Speak Up Africa!, an international nonprofit for public health policy and advocacy based in Senegal, has written about Africans’ ownership of their health systems. She says that while the need remains great for researchers to innovate new treatments, it can be a challenge “to make the argument for that investment in research when there are so many critical needs in the health system.” There needs to be a balance, she says, between doing the research and ensuring that communities can access needed health services.
Success will require “a combination of existing interventions, targeted interventions,” she says, along with new innovations like successful vaccines, and ensuring their delivery “in a way that is most impactful and saves the most lives.”
Diop Djibo is optimistic. “We have multiple [malaria] vaccines now at different stages, and it’s very encouraging,” she says. “I believe that we can get to zero by 2030. But I also believe that will require the combination of all existing interventions, exploring these new interventions and fast-tracking them.” The progress of the past two decades is encouraging but it’s not enough. A successful vaccine will be critically important, she says.
Owning the process for innovation is important, says Stephanie James, senior scientific advisor at the Foundation for the National Institutes of Health (FNIH), a nonprofit supporter of NIH. “In my experience, African authorities and citizenry want to know that there is substantial local input into the new technologies. The best way to achieve this is through co-ownership and co-development,” she says.
“We've tested so many vaccines, and many of them failed,” says Djimdé. “But we have learned in the process, and we have learned how to do it right.”
The next step, phase 3 clinical trials, will prove crucial for the promising vaccines. Typically this stage takes a year to yield results.
True to his mentor’s spirit, Djimdé places trust more in the scientific method than in any individual product. “If the vaccine is good, we can show it. If it’s bad, we'll show that as well.”