Tropical diseases like Chagas affect one billion people. Why don’t we have better drugs?
Earlier this year, the CBC reported that Canadian international development funding was being used to deliver homeopathic treatments to patients with Chagas disease (American trypanosomiasis) in Honduras. Medical experts were quick to raise serious concerns about public funds being used to help deliver unproven treatments to vulnerable people who are sick with a potentially fatal disease. In response, the Minister responsible announced that Canada would no longer be providing funding for homeopathy as part of its international development programming.
The medical community is right to be concerned: As many as 6–7 million people are estimated to be infected with Trypanosoma cruzi, the parasite that causes Chagas disease, which is transmitted by the bite of “kissing bugs” or from infected mothers to their babies, and can cause heart failure, among other complications. The medicines currently available to treat Chagas disease, benznidazole and nifurtimox, are more than 40 years old, and as currently administered, require long treatment courses and have significant side effects. Today, less than one percent of patients with Chagas in need of treatment are receiving it. We need both an improved understanding of how to optimize the safety and effectiveness of the current drugs, and eventually, newer, improved medicines.
But amid the outrage that the CBC articles on homeopathy have provoked, we must not lose sight of the bigger picture.
Chagas is just one of 20 different diseases considered by the World Health Organization to be Neglected Tropical Diseases, or NTDs. This diverse group includes rabies, snakebite envenoming, leishmaniasis and others—diseases for which available treatments are often ineffective, toxic or absent altogether. This neglect persists despite more than one billion people around the world being affected by NTDs.
And yet, evidence from over a decade of research and development (R&D) for neglected tropical diseases shows that new medicines—and new formulations of existing medicines—can be developed and delivered affordably and efficiently. Take sleeping sickness (or Human African trypanosomiasis, the African form of Chagas disease): It is endemic in 36 African countries, but until recently, the most effective treatment was a combination of two medicines that, among other things, required patients to be hospitalized in order to receive infusions of the drugs over many days and undergo invasive testing to determine the disease stage. This replaced a more toxic drug, melarsoprol, that was derived from arsenic and killed roughly one in 20 patients who received it.
But beginning in 2005, the Drugs for Neglected Diseases Initiative (DNDi) identified a promising, previously abandoned medicine called fexinidazole and conducted a series of randomized trials in the Democratic Republic of Congo and Central African Republic. DNDi is a not-for-profit pharmaceutical research and development organization founded by seven founding partners that initiates and coordinates R&D with an international research community of scientists, the public sector, the pharmaceutical industry, and other partners—without having labs or manufacturing facilities of their own. On the basis of their studies, in 2018 the European Medicines Agency recommended fexinidazole for the treatment of sleeping sickness and it is a game changer: It is an all-oral cure taken over 10 days, rather than an infusion or an arsenic-based treatment, which treats both stages of the disease.
DNDi has also developed treatment protocols for and delivered seven other treatments, which include a new pediatric formulation of benznidazole for Chagas, two fixed-dose combinations of anti-malarial drugs, and new treatment regimens for visceral leishmaniasis, among others.
The R&D model that DNDi uses prioritizes patients’ needs by, first, prioritizing diseases where patient needs are glaring or which pose a significant public health burden, and second, developing formulations that are adapted to patients’ needs such as fixed-dose combinations, pediatric formulations, and shorter treatment regimens. DNDi makes scientific data freely available, reports openly on R&D costs, and applies policies that ensure the medicines they develop are priced affordably. Through a more flexible, principled model, DNDi reports they can develop a new medicine for approximately CAD $150–225 million and improve an existing treatment for between CAD $13–60 million—a far cry from the billions the private sector says it costs them.
But NTDs are the “canary in the coalmine”—a signal that something is majorly wrong with the way that medicines are being developed and made available (or not) for patients. Drugs are increasingly becoming unaffordable for patients and health systems in Canada and virtually every other country around the world. Policymakers are wrestling with how best to respond to the epidemic of high prices, but unless we change the way that drugs are developed in the first place and experiment with new models of R&D—like DNDi —that can better ensure patient access to and affordability of final products and make data available (and R&D costs transparent), we’ll miss the big picture.
Canadians should rightfully be upset about ineffective treatments being used to treat Chagas disease, but they should also be outraged that this happens every day, for neglected tropical diseases that affect close to a billion people. Fixing this problem requires us to think beyond any one disease, and requires us to rethink the way new medicines are discovered and delivered in the first place. We need to ensure that our R&D systems prioritize patient needs over profits, that they promote collaboration over competition, and that they deliver effective, timely, and affordable medicines to patients, whether they are in Canada, Honduras or anywhere else.
Dr. Jason Nickerson, RRT, Ph.D., is a Humanitarian Affairs Advisor for Doctors Without Borders/Médecins Sans Frontières in Ottawa.