A new single‑dose oral drug, acoziborole, may transform the fight against sleeping sickness and help the World Health Organization reach its goal of elimination by 2030. A committee of the European Medicines Agency has given a substantial positive opinion on the medicine, which could become available as soon as next year.
Acoziborole is taken as three pills swallowed together in a single administration. It replaces much more demanding older therapies that required intravenous infusions, sometimes causing severe vein pain and carrying an approximate 5% treatment‑related fatality rate. The current oral first‑line drug, fexinidazole, must be taken for 10 days and can cause nausea, vomiting and disturbances in heart rhythm. Clinical trials of acoziborole reported only one notable adverse effect: mostly mild to moderate headaches.
For decades, treatments for human African trypanosomiasis were difficult to deliver, requiring trained staff, equipment and reliable infrastructure—resources often missing in the remote rural areas where most cases occur. The simplicity and tolerability of acoziborole should considerably ease patient care, broaden access to treatment and speed progress toward elimination, according to WHO experts involved in the program.
Acoziborole was developed by the Drugs for Neglected Diseases initiative (DNDi) in partnership with Sanofi and funders including the Gates Foundation. DNDi began work on sleeping sickness in 2003 to tackle conditions that commercial drug developers had little financial incentive to pursue. Researchers involved in the trials note that severe side effects from past drugs discouraged people from seeking care; a well‑tolerated, single‑dose medicine should remove a major barrier to treatment uptake.
Sleeping sickness is caused by the parasite Trypanosoma brucei gambiense, transmitted by the tsetse fly. The insect thrives in warm savanna woodlands and in vegetation along lakes and streams, so cases cluster in remote communities that rely on fishing, hunting and agriculture. “Like many tropical diseases, sleeping sickness affects poor, rural populations,” a disease specialist observed.
Sustained control efforts—tsetse control, improved diagnostics and treatment—have driven down deaths dramatically. Worldwide, reported cases are now around 1,000 a year, with nearly two‑thirds occurring in the Democratic Republic of Congo (DRC). But experts warn the disease has rebounded historically and remains a threat if surveillance and resources lapse.
The illness has two stages. The early stage causes fever and headache; if the parasite crosses the blood–brain barrier it produces a late stage with neurological symptoms such as confusion, seizures and disrupted sleep–wake cycles—the feature that gives the disease its common name. Without treatment the disease can progress to coma and death. Acoziborole has shown activity against both early and late stages.
DNDi clinicians call the drug “transformative.” Trials in South Ubangi province in the DRC were conducted under difficult conditions—no reliable electricity or water, limited transport and a need to train health workers and install internet and power for laboratory testing—but local researchers and participating patients were essential to the work. Ongoing research led by trial teams is evaluating whether rapid serologic blood tests can be accurate enough to allow treatment to begin the same day in the field rather than waiting for more complex confirmatory testing. If testing and treatment can be done immediately, more infected people could be treated and human reservoirs reduced, potentially interrupting transmission.
Next steps include formal review by the DRC Ministry of Health and WHO to decide whether national and international treatment guidelines should be updated, which will help authorization in other affected countries. Observers caution that future cuts to U.S. or other Western funding could hinder access in the places that need the drug most.
Reported by Fran Kritz.