Trypanosoma brucei, the parasite causing sleeping sickness

CDC

Preliminary results from a sleeping sickness treatment trial have been so overwhelmingly positive that doctors working in two African nations want the combined medication available as soon as possible.

And more patients — beyond the number needed — are being enrolled on the trial in order to make the treatment available.

Victor Kande, director of the national control programme for the disease in the Democratic Republic of Congo (DRC), says that he would like more patients to benefit from the treatment by enrolling in the trial before it is completed next year.

"The DRC is encouraging people to be enrolled under the ongoing clinical trials as the results to date have been so encouraging for the new treatment," says Kande. "After sufficient documentation, the DRC will be ready to recommend it as a treatment accessible to all."

The trials test the effectiveness of combining two drugs, eflornithine and nifurtimox, against sleeping sickness. Trials began in Congo-Brazzaville and have since expanded to three sites in the DRC and two in Uganda.

Mid-way results, after 18 months follow-up on the first 103 patients enrolled at the Congo Brazzaville site, have impressed the National Programme for Sleeping Sickness Control in the DRC, who wish to increase access.

Without being enrolled in trials, patients have no access to nifurtimox as it is only licensed for use against Chagas disease, a related parasitic infection. As a result, extra patients are being enrolled.

According to Girardo Priotto of Doctors Without Borders, "The situation is so desperate in the field that we are not happy with two more years of waiting for the final results of the current trial, so we are looking for ways of extending access to this treatment through additional studies."

Nifurtimox is donated free to the World Health Organisation (WHO) by pharmaceutical company Bayer. But without further scientific evidence the WHO will not agree to its use for sleeping sickness. Other studies have also supported the use of nifurtimox-containing combination therapies for sleeping sickness.

Thousands of people each year are diagnosed with advanced-stage sleeping sickness, which is fatal if not treated. Current treatment, with the drug melarsoprol, itself causes the death of around six per cent of patients. In addition, some patients are also resistant.