Post date: Sep 19, 2012 3:50:14 PM
MALINDI, KENYA (REUTERS) - Carried by the female anopheles mosquito, the parasites that cause malaria have perplexed scientists for generations. Conventional treatments that rely on multiple drugs are effective but only until the parasites develop a resistance to them.
Researchers at the University of Cape Town say they may be close to producing a cure for malaria following the discovery of a compound that disrupts the malaria parasite's life cycle in animal models, effectively destroying it. The researchers are optimistic that future trials will demonstrate the compound's efficacy in humans.
Researchers at the University of Cape Town (UCT) however, now say that's about to change. They have developed a single-dose anti-malarial drug they say kills the resistant parasites instantly, potentially charting a new path in the eradication of malaria.
Malaria accounts for majority of deaths in Africa. At the core of the drug is a molecular compound from the aminopyridine class, code named MMV390048.
The scientists say that in animal models, the compound disrupted the malaria parasite's life cycle, effectively killing it and curing its host of the disease. They say the treatment will also prevent person-to-person transmission of the parasites through contaminated blood.
The university's Drug Discovery and Development Centre (H3-D) and Swiss-based Medicines for Malaria Venture (MMV) collaborated to test the compound on animals. Lead researcher, Professor Kelly Chibale says the results were remarkable.
"The main difference between this molecule that we have discovered in comparison to drugs or medicines that are on the market already are basically at two levels. Firstly, unlike existing that are available on the market, when tested in the same animal model or experiments, what we found was this molecule we have discovered is far superior in terms of actually curing animals infected with the malaria parasite just with a single low dose of the drug," said Chibale.
World Health Organisation data shows that malaria killed about 655,000 people worldwide in 2010, majority of whom were in sub-Saharan Africa. Malaria is responsible for one in five childhood deaths.
Malaria symptoms include fever, vomiting and muscle pain. If left untreated, the disease leads to organ breakdown and death.
The research team spent 18 months testing the molecules on mice. Chibale says during that time, the parasites showed no signs of developing resistance to the compound.
"What we then did was to go through a process to confirm whether what we saw from this high-throughput screening campaign of 40,000 molecules to prove that what we found was not false we undertook a process what we call heat validation and this is just a process where we remake, we characterise by techniques that we know to confirm that this molecule is real. We check the purity, we retest on the parasite and we retest on the normal cells and then that allowed us to confirm that what we saw from this throughboid screening campaign was genuine," said Chibale.
The MMV Expert Scientific Advisory Committee (ESAC) has selected the compound for pre-clinical development, a first for research conducted on African soil.
Professor Lucille Blumberg, Deputy-Director at South Africa's National Institute for Communicable Diseases says she's thrilled and optimistic about the new drug.
"I think it's a hugely significant find that this drug has been identified in an African research program. I think UCT needs to be congratulated. It's a new class of drugs so cross resistant malaria drugs which parasites may develop resistance at some time is not going to be a problem, so I think that particularly is going to be important and seems to be a very potent drug." said Blumberg.
Besides the huge human cost imposed on the African continent, the mosquito-borne disease is an economic burden, draining public and private resources and hampering productivity.
In Nigeria, Africa's most populous nation, malaria is responsible for up to 25 worker days lost per person per year.
In Zambia, it is the leading cause of absenteeism, accounting for more than twice as many days off as HIV/AIDS, and can consume up to 40 percent of the public health budget in cash-strapped frontline states.
The University of Cape Town's drug has a long path of further testing ahead of it, including clinical trials on humans which may take more than five years but the researchers are confident their discovery will reach the market and transform lives wherever malaria exists.