Ancient Cure Could Beat Malaria
LONDON- A new malaria drug based on a traditional Chinese remedy promises the biggest breakthrough in a generation against the world’s second most deadly infectious disease after Aids, scientists said yesterday.
Animal and computer studies of the therapy, known as OZ227 or OZ, suggest that it will be the most potent and effective weapon yet developed against malaria, which kills a million people a year and infects up to 500 million more.
Safety tests in Britain have already shown that OZ has no significant side-effects, and clinical trials of its effectiveness in patients are to begin in Africa and Thailand next year.
If these go as well as scientists expect, the drug could be given to people with the disease within four years.
OZ is modelled on the action of the most effective known anti-malarial, a Chinese herbal medicine called artemisinin extracted from the sweet wormwood plant, Artemisia annua.
Although artemisinin-based drugs are currently the best available treatment for the disease, the high cost of the refinement process makes them up to 20 times more expensive than standard therapies. This generally puts them beyond the means of poor countries in Africa, South America and Asia, where malaria is endemic.
The new drug, developed by a partnership between the non-profit Medicines for Malaria Venture (MMV) and Ranbaxy, an Indian pharmaceutical company, is modelled on the molecular structure of artemisinin and kills the malaria parasite in exactly the same way. Research indicates that its antimalarial action is even more powerful.
OZ is entirely synthetic, and can thus be mass-produced much more cheaply than natural artemisinin, without the need to extract chemicals from a plant. It also has a longer shelf life than the natural drug, and fewer doses are needed to produce its full effects.
“This could be the biggest breakthrough in malaria treatment in our generation,” Christopher Hentschel, chief executive of MMV, said.
“The need to develop a low-cost, potent synthetic antimalarial drug is more urgent than ever. This project has surpassed our expectations. The animal models are quite predictive and they show that the drug is very very potent, much more potent than anything else we have seen.
“We already know that this class of drug works, so the risk it won’t work in humans is very low. The data for this particular group are very convincing indeed.”
Brian Tempest, chief executive of Ranbaxy, said: “Our scientists are excited to be able to work on a drug that could save millions of lives.”
Malaria kills more people worldwide than any infectious disease apart from Aids, and is the leading cause of death among children in sub-Saharan Africa. An estimated 2 billion people — a third of the world’s population — live in regions where it is endemic.
The annual cost of the disease in Africa, where it is most prevalent and deadly, is $12 billion (£6.5 billion) in lost GDP, and it consumes 40 per cent of African health budgets.
The disease is caused by the Plasmodium falciparum parasite, and is transmitted to humans via mosquitoes of the genus Anopheles. The species Anopheles gambiae is the most dangerous vector.
Efforts to control malaria have foundered in recent years because of the parasite’s growing resistance to traditional drugs. Chloroquine, the cheapest and most common treatment, is now 90 per cent useless in sub-Saharan Africa.
OZ was developed by an international team led by Jonathan Vennerstrom of the University of Nebraska, who used artemisinin as a template to create a “wish list” of properties that an ideal antimalarial drug should have.
Sophisticated computer models were then used to generate thousands of candidate molecules, the most effective of which was OZ. Details of the research are published today in the journal Nature.
The drug is the most significant advance yet for the MMV, which spends $30 million a year on malaria research. It is largely funded by the public and philanthropic sector. The Bill & Melinda Gates Foundation is its largest private donor, and Britain its most significant government supporter.
Independent malaria experts said that the drug was an exciting advance, although they cautioned against excessive optimism before the trials are complete.
Brian Greenwood, Professor of Tropical Medicine at the London School of Hygiene and Tropical Medicine, said: “The most promising new drug for treatment, derived from a plant called Artemisia annua, is now being used more frequently, but making it is difficult and expensive.
“This is because the plant takes about 18 months to grow and then the drug needs to be extracted. This new research has produced a drug very similar to that from plants, but without the time and expense of waiting for the plant to grow and extracting the compound. This should make the drug easier to produce and less expensive.”
Robert Sinden, Professor of Parasite Cell Biology at Imperial College, said: “The discovery of a method for the direct chemical synthesis of this family of compounds, which has the potential to reduce the production costs, and therefore increase the availability, of these drugs is a major step forward.
“However, the fight is not over; resistance to these drugs will evolve, and the search for new drugs, vaccines and other measures to halt transmission of this expanding disease must be pursued with vigour.”
Animal and computer studies of the therapy, known as OZ227 or OZ, suggest that it will be the most potent and effective weapon yet developed against malaria, which kills a million people a year and infects up to 500 million more.
Safety tests in Britain have already shown that OZ has no significant side-effects, and clinical trials of its effectiveness in patients are to begin in Africa and Thailand next year.
If these go as well as scientists expect, the drug could be given to people with the disease within four years.
OZ is modelled on the action of the most effective known anti-malarial, a Chinese herbal medicine called artemisinin extracted from the sweet wormwood plant, Artemisia annua.
Although artemisinin-based drugs are currently the best available treatment for the disease, the high cost of the refinement process makes them up to 20 times more expensive than standard therapies. This generally puts them beyond the means of poor countries in Africa, South America and Asia, where malaria is endemic.
The new drug, developed by a partnership between the non-profit Medicines for Malaria Venture (MMV) and Ranbaxy, an Indian pharmaceutical company, is modelled on the molecular structure of artemisinin and kills the malaria parasite in exactly the same way. Research indicates that its antimalarial action is even more powerful.
OZ is entirely synthetic, and can thus be mass-produced much more cheaply than natural artemisinin, without the need to extract chemicals from a plant. It also has a longer shelf life than the natural drug, and fewer doses are needed to produce its full effects.
“This could be the biggest breakthrough in malaria treatment in our generation,” Christopher Hentschel, chief executive of MMV, said.
“The need to develop a low-cost, potent synthetic antimalarial drug is more urgent than ever. This project has surpassed our expectations. The animal models are quite predictive and they show that the drug is very very potent, much more potent than anything else we have seen.
“We already know that this class of drug works, so the risk it won’t work in humans is very low. The data for this particular group are very convincing indeed.”
Brian Tempest, chief executive of Ranbaxy, said: “Our scientists are excited to be able to work on a drug that could save millions of lives.”
Malaria kills more people worldwide than any infectious disease apart from Aids, and is the leading cause of death among children in sub-Saharan Africa. An estimated 2 billion people — a third of the world’s population — live in regions where it is endemic.
The annual cost of the disease in Africa, where it is most prevalent and deadly, is $12 billion (£6.5 billion) in lost GDP, and it consumes 40 per cent of African health budgets.
The disease is caused by the Plasmodium falciparum parasite, and is transmitted to humans via mosquitoes of the genus Anopheles. The species Anopheles gambiae is the most dangerous vector.
Efforts to control malaria have foundered in recent years because of the parasite’s growing resistance to traditional drugs. Chloroquine, the cheapest and most common treatment, is now 90 per cent useless in sub-Saharan Africa.
OZ was developed by an international team led by Jonathan Vennerstrom of the University of Nebraska, who used artemisinin as a template to create a “wish list” of properties that an ideal antimalarial drug should have.
Sophisticated computer models were then used to generate thousands of candidate molecules, the most effective of which was OZ. Details of the research are published today in the journal Nature.
The drug is the most significant advance yet for the MMV, which spends $30 million a year on malaria research. It is largely funded by the public and philanthropic sector. The Bill & Melinda Gates Foundation is its largest private donor, and Britain its most significant government supporter.
Independent malaria experts said that the drug was an exciting advance, although they cautioned against excessive optimism before the trials are complete.
Brian Greenwood, Professor of Tropical Medicine at the London School of Hygiene and Tropical Medicine, said: “The most promising new drug for treatment, derived from a plant called Artemisia annua, is now being used more frequently, but making it is difficult and expensive.
“This is because the plant takes about 18 months to grow and then the drug needs to be extracted. This new research has produced a drug very similar to that from plants, but without the time and expense of waiting for the plant to grow and extracting the compound. This should make the drug easier to produce and less expensive.”
Robert Sinden, Professor of Parasite Cell Biology at Imperial College, said: “The discovery of a method for the direct chemical synthesis of this family of compounds, which has the potential to reduce the production costs, and therefore increase the availability, of these drugs is a major step forward.
“However, the fight is not over; resistance to these drugs will evolve, and the search for new drugs, vaccines and other measures to halt transmission of this expanding disease must be pursued with vigour.”
posted by Kruger2Canyons.com at
Thursday, August 19, 2004
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