Research at the University of York indicates that parasitic diseases apparently kill a massive population of Africans every year. The ongoing research is being carried out in collaboration with scientists in Dundee and Toronto. They seem to have cracked the code to tackle such diseases with a new treatment.
The treatment is targeted to fight the disease, human African trypanosomiasis (HAT), commonly referred to as sleeping sickness. The research appears to support development of an effective, low toxicity drug that can be administered orally. The HAT disease affects approximately fifty to seventy thousand people in sub-urban Africa. The disease spreads via the Tsetse fly, which affects the brain thereby causing an imbalance in the sleep cycle of the patient.
The second stage of this disease appears to be the most difficult to treat especially in poverty-stricken areas. Of the two drugs available, the arsenic-based drug seems to have fatal side-effects in at least one out of every 20 patients being treated with the drug. The other drug, eflornithine, is not effective against all forms of the disease and requires prolonged hospital treatment. Moreover, the cost of the drug hampers its usage. Scientists are worried about not having an effective treatment for this fatal disease, as the existing treatments keep yielding failures.
To devise new and safe treatments, the team from York’s Centre for Immunology and Infection (CII), working in collaboration with the University of Dundee Drug Discovery Unit (DDU), and the University of Toronto’s Structural Genomics Consortium (SGC), appear to have made substantial progress in developing compounds. These compounds seem to have proved effective in killing the parasites, especially in stage one of the disease. The compound acts against the enzyme N-myristoyl transferase (NMT) which is necessary for the survival and growth of the parasite.
The research team led by Professor Debbie Smith, originally identified NMT as a potential drug target for HAT. Along with her colleagues in the York Structural Biology Laboratory, the team also developed the essay and materials for screening in Dundee.
Prof. Smith commented that, “We are excited that our research has contributed to development of a novel compound that kills parasites, an important step in developing new therapeutics against this neglected tropical disease. Our early proof-of-principle studies together with recent definitive experiments confirming the specificity of the new compounds confirm the importance of working collaboratively in the quest for new drugs in this area.”
Professor Paul Wyatt, Director of the Drug Discovery for Tropical Diseases program at Dundee, had to say that, “This is one of the most significant findings made in recent years in terms of drug discovery and development for neglected diseases. 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.”
The scientists seem quite certain about the drugs they have discovered to treat the first stage of the disease. Following this success, the scientists feel that they may be able to find a cure for the second stage as well. Dr. Dr Ray Hui’s team alongside SGC, at the University of Toronto, designed a three-dimensional model on the interaction of the new molecules with NMT. With this information, the scientists can produce better compounds and thereby speed the discovery of new drug candidates.
With decreasing efficiency of the current stage two drugs, the World Health Organization is trying to focus solely on treatments for the second stage. The team has also shifted its focus to work out solutions for the second, more serious stage of the disease.
The African sleeping sickness is apparently neglected by large pharmaceutical companies. The reason behind this seems to be that the shareholder value driven model of the big companies does not work well in the sub-Saharan Africa where people cannot afford costly medicines.
The findings of the research were published in the latest edition of the journal, Nature.