Scientists ready to tackle African sleeping sickness
Groundbreaking research from Canada and the UK has given scientists the edge they need to identify new treatments for the fatal African trypanosomiasis (HAT) known as sleeping sickness. The disease impacts the lives of thousands of Africans each year and is the cause of hundreds of deaths. The scientists present their novel approach in the journal Nature, HAT is a parasitic disease that is eventually fatal. Parasites infect the brain affecting the patient's sleep cycle.
The scientists, from the University of Dundee and the University of York in the UK and the Structural Genomics Consortium in Canada, said their research could potentially lead to the development of new and effective medications for treatment of sleeping sickness. These new drugs could be administered orally and are also low in toxicity.
According to the World Health Organization (WHO), HAT, which is spread by the bite of a tsetse fly, affects between 50 000 to 70 000 people in sub-Saharan Africa. Doctors currently use two drugs to treat patients; the side effects of one result in the death of 5% of those treated, while the other burns bigger holes in people's pockets, results in longer hospital stays and does not always make patients better.
'This is one of the most significant findings made in recent years in terms of drug discovery and development for neglected diseases,' explained Professor Paul Wyatt, Director of the Drug Discovery for Tropical Diseases programme at Dundee University.
'We now have a valid drug target for HAT and have found leads for drugs which can be dosed orally. These two findings represent significant strides in the development of a full blown drug against sleeping sickness suitable for clinical trials,' he added.
'HAT comes in two stages — we know the drug leads we have identified in this paper can treat the first stage and we are very optimistic that we can now further develop them to treat the second, more serious stage.' The scientists believe that the drugs can be ready for human clinical trials in around 18 months.
'This is a significant discovery,' remarked Dr Shing Chang, Research and Development (R&D) Director of the Drugs for Neglected Diseases Initiative. 'It is a good example of applying state of the art scientific knowledge and tools in a collaborative effort to address the unmet needs of neglected patients.'
Professor Wyatt noted that the scientists must overcome some hurdles in order to develop new drugs. 'The first is identifying an Achilles heel of the parasite, such as an enzyme which is essential for the survival of the parasites, known as a drug target,' he explained. 'The second is to confirm that molecules can disrupt these targets and so kill the parasite, a process called 'target validation'. The next is 'lead optimisation' to develop these early molecules into candidate drugs for clinical trials,' he added. 'This is where we are now. The final hurdle is to show safety and efficacy of the new drug in patients.'