Results from a clinical trial evaluating new drug combinations for sleeping sickness, carried out by the international humanitarian medical aid agency Medecins Sans Frontieres (MSF), and its research arm, Epicentre, have now been published in the journal PLoS Clinical Trials.
African trypanosomiasis, or sleeping sickness affects many tens of thousands of people each year in sub-Saharan Africa and is a serious disease for which there are few treatment options. The most commonly used drug, Melarsoprol, is highly toxic. MSF and Epicentre jointly carried out a trial that started in 2001 in Uganda to evaluate the efficacy and safety of three drug combinations for this disease. The aim was to find out if any of these combinations would provide a viable treatment option for patients with second-stage sleeping sickness, where infection has reached the brain and prognosis is normally very poor. In the trial, the drug combinations compared were melarsoprol-nifurtimox, melarsoprol-eflornithine, and nifurtimox-eflornithine. However, once 54 patients had been recruited (435 were planned), it was obvious that the death rate was much higher amongst individuals receiving one of the combinations, so the trial was stopped.
In the trial, the cure rate for nifurtimox-eflornithine was over twice that for melarsoprol-nifurtimox and substantially higher than that for melarsoprol-eflornithine. The rates of adverse events were also lower for patients treated with nifurtimox-eflornithine. These findings are encouraging and suggest that the nifurtimox-eflornithine combination has potential as a future therapy for second-stage African trypanosomiasis, and should be evaluated further in clinical trials.