Washington: Glasgow scientists have in a new study presented a key advance in developing a safer cure for sleeping sickness.
Led by Professor Peter Kennedy, researchers at the University of Glasgow’s Institute for Infection, Immunology and Inflammation have created a version of the drug most commonly used to treat sleeping sickness, which can be administered orally in pill form.
Sleeping sickness, or human African trypanosomiasis (HAT), is a neglected tropical disease of major importance. Transmitted by the tsetse fly and caused by the trypanosome parasite, sleeping sickness is invariably fatal if left untreated.
Once the disease has crossed the blood-brain barrier and entered the central nervous system the most commonly used treatment is an intravenous course of the arsenic-based drug melarsoprol.
Because melarsoprol has a low solubility in water, it is dissolved in propylene glycol and administered intravenously. The result is a highly toxic drug that kills five percent of patients receiving it and leaves many others permanently brain-damaged.
Researchers at the University of Glasgow combined melarsoprol with cyclodextrins – molecules that surrounded the drug allowing it to be administered orally, increasing its solubility and releasing the drug more slowly in the gut.
In laboratory tests the altered drug was shown to retain its ability to kill the infection, and was able to cure mice infected with the parasite after a seven-day daily oral dosing schedule.
The drug cleared parasites from the brain and restored normal blood-brain barrier integrity.
“This new research is the most clinically important in the 20 years of our trypanosome research group,” Prof. Kennedy said.
“It has the potential of a major therapeutic advance and if it is equally effective in humans then it would also have a significant socio-economic impact because the duration of inpatient treatment would be shorter and some patients might even be eventually treated at home,” he stated.
The findings have been published in the open-access journal PLoS Neglected Tropical Diseases on September 6.