A more efficient and selective method of treating malaria disease.
The world urgently needs new, effective antimalarial treatments. Across the globe, 3.4 billion people live in areas where they are at risk for malaria transmission. Malaria is present in more than 100 countries, and in 2013, the World Health Organization estimated 198 million cases occurred worldwide, killing 500,000 people, mostly children and mostly in sub-Saharan Africa. Malaria parasites are from the genus Plasmodium. Four species commonly infect humans: P. falciparum, P. vivax, P. ovale, and P. malariae. However, with a global distribution, P.falciparum is the most deadly and is also the most common type of malarial infection in Africa. Though serious, malaria is generally treatable. However, doctors increasingly face malaria that is resistant to commonly used drugs such as chloroquine and artemisinins.
Tyrothricin is a natural antibiotic compound produced by a soil bacterium (Bacillus aneurinolyticus). Scientists reported its antimalarial activity in 1944, but further research into its component molecules, the tyrocidines, only started recently. In 2007, Stellenbosch Professor Marina Rautenbach and colleagues published a promising investigation into the anti- malarial properties of tyrocidine peptides against P. falciparum infected blood cells. Unfortunately, tyrocidines don’t make good anti-malarial drugs because, besides disrupting the malaria parasite’s life cycle, they are also toxic to humans, causing healthy red blood cells to rupture.
Researchers at Stellenbosch University have now developed a method of administering the tyrocidines to patients in a manner that does not affect the healthy cells, thereby killing the malaria parasite without being toxic to the patient.
Tyrocidines prepared according to the method of the present invention may be used to treat malaria and may be especially important in treating strains resistant to traditional drugs. The preparation is not toxic to healthy red blood cells and is able to kill the malaria parasite at much lower concentrations than normal preparations of tyrocidines.
As common treatment with traditional anti malaria drugs such as chloroquine and artemisinins lead to drug-resistant malaria strains, novel treatments such as the tyrocidine preparation discussed herein will be essential. The preparation is 500 times more efficient and 100 times more selective than conventional tyrocidine. It also prevents reinfection of blood cells for 48 hours.
The tyrocidine preparation has been tested in antimalaria and hemolysis assays. Efficiency and selectivity of the prepartion have been shown in a standard in vitro anti- malaria assay against a chloroquin-resistant malaria strain, and animal tests are currently being conducted.
Professor Lubertus Klumperman, Department of Chemistry and Polymer Science, Stellenbosch University