عمومی | science mag

A ‘rediscovered’ drug against sleeping sickness gets the green light

A powerful new treatment for human African trypanosomiasis, better known as sleeping sickness, received a stamp of approval today from the European Medicines Agency (EMA) in London, clearing the way for countries affected by the disease to approve its use. That could soon improve the lives of thousands of patients in West and Central Africa where sleeping sickness, caused by a parasite that is transmitted by the tsetse fly, not only causes severe disruption in sleep patterns but also aggression, psychosis, and ultimately death.

“It’s a great victory for people in Africa with sleeping sickness, but it is also a victory for” the Drugs for Neglected Diseases initiative (DNDi), the non-profit organization that rediscovered the drug and is shepherding it to approval, says Peter Hotez, a tropical disease expert at Baylor College of Medicine in Houston, Texas. “It’s a great validation of DNDi’s approach.”

Health officials reported 1447 cases of human African trypanosomiasis to the World Health Organization (WHO) last year, but the true number of cases is widely believed to be much higher. As recently as 10 years ago, the main treatment for human African trypanosomiasis was an arsenic-based drug named melarsoprol that killed 5% of those treated with it. Current treatments with drugs named eflornithine and nifurtimox aren’t deadly, but they involve a complicated series of infusions and pills that have to be administered in a hospital; they also require patients to undergo painful lumbar punctures in order to check if the parasite is present in the spinal fluid. All of that puts the treatments out of reach for many patients in countries where most of the cases occur: the Democratic Republic of the Congo, the Central African Republic, Guinea, and Chad.

The new drug, fexinidazole, can be taken as a once-a-day pill for 10 days. Originally developed in the 1980s, fexinidazole had been abandoned by Hoechst, the German company that owned it; it was rediscovered in 2005 by DNDi researchers looking for possible anti-parasitic compounds. DNDi cooperated with drug maker Sanofi to test the drug in patients and apply for an EMA recommendation under a special set of rules designed to help get new drugs on the market in low- and middle-income countries outside the European Union. The so-called Article 58 procedure involves experts from EMA, WHO, and affected countries.

Today an EMA scientific committee announced its “positive opinion” for fexinidazole, opening the way for individual countries to approve its use, which should happen within 90 days. DNDi says the first patients should be able to receive the drug by mid-2019.

That’s great news on several levels, says Nathalie Strub-Wourgraft, director of neglected tropical diseases at DNDi, which is based in Geneva, Switzerland. Since patients don’t have to travel for treatment, they can be cured earlier, which benefits not only them but also helps slow the spread of the disease. The drug is effective for both mild and severe forms of sleeping sickness, so health workers no longer have to test patients’ spinal fluid. And the fact that patients don’t need to be hospitalized will reduce pressure on scarce hospital beds and staff in poor countries.

The treatment also renews hopes that the disease could be eliminated completely, Hotez says, but it will require a concerted effort. “We’ve been here before,” he says. In the 1960s, “sleeping sickness was at its nadir,” but wars in affected areas undid much of the progress. The world should not miss this new opportunity to finally conquer the disease, he says. “There will be future conflicts in Africa.”