HEALTH: Thai Clinical Trials May Hold Key to Malaria Control

By Marwaan Macan-Markar Reprint | | Print |

Marwaan Macan-Markar

BANGKOK, Jul 9 2005 (IPS) - Every two weeks, without fail, Sornchai Looareesuwan leaves the Thai capital on a mission that takes him to a province in the north-west of this country. For it is there, in Mae Sot, that he is conducting trials for a new anti-malarial drug.

This effort by Sornchai, a professor at the faculty of tropical medicine at Bangkok’s Mahidol University, is for only one of at least four possible new anti-malarial drugs that he and his 38-member team of doctors, nurses and researchers are involved in developing.

”These are very promising candidates,” the somewhat excitable Sornchai said in his office that is full of records reflecting his many achievements as one of Thailand’s leading authorities on drugs to treat malaria. ”They should be ready in the next two to five years.”

Among these prospective candidates is an oral drug, labeled ‘DB289’, that is undergoing its second trial, for which 120 patients have been enrolled.

During the first phase trials of one of the drugs Sornchai’s team tested 78 malaria patients and there were impressive results, affirmed by reports in the local press. ”The drug proved to be effective and could curb the disease within three days,” said one report.

The Mae Sot chapter to develop a range of new drugs to save malaria patients from death is only the latest in Mahidol University’s over 30- year involvement on the frontlines in the battle against malaria.

”Mahidol is critically important,” Anna Wang, spokeswoman of the Geneva- based Medicines for Malaria Venture, a non-governmental group involved in research and development of anti-malarial drugs, told IPS. ”Most of the drugs we develop will at some point be tested there.”

Currently, clinical trials for anti-malarial drugs are being conducted in over 12 countries, besides Thailand. They range from Laos, Cambodia, Indonesia and China, in Asia, to Senegal, Burkina Faso, Kenya and Zambia, in Africa.

In all, the MMV says that there are 21 drug candidates in the pipeline, in addition to 24 vaccine candidates.

The urgency to find a potent remedy for malaria comes in the wake of new data revealed early this year that over half a billion people are infected by the killer disease every year, which is nearly twice the number that was considered the annual infection rate by public health organisations.

The new findings, published in a March issue of ‘Nature,’ said that while global outbreaks of malaria were almost 50 percent higher than what the World Health Organisation (WHO) estimates, new cases outside Africa were 200 percent higher.

Till the appearance of these numbers, produced by a research team led by the well-respected epidemiologist Robert Snow, the WHO has stated that some 369 million people are infected by malaria every year, with the bulk of this mosquito-borne disease occurring in Africa.

According to the Geneva-based U.N. agency, close to 1.2 million people die every year from malaria, 90 percent of whom are children under five years and mostly in sub-Saharan Africa.

Seen in another way, it means 3,000 children are killed every day by malaria, says the WHO.

Such a high death rate stems from the world lacking a potent medicine to combat the disease, in particular after the standard medication, chloroquine, has proved ineffective after almost 40 years of use.

That is due to a drug-resistant strain of the malaria-causing parasite, plasmodium falciparum emerging in Africa and then spreading across the world.

Studies reported in one medical journal have shown that there was a marked increase in malaria mortality in eastern and southern Africa. The numbers almost doubled over the period 1992-1998 compared with 1982- 1989 – possibly as a result of increasing resistance to chloroquine.

On top of that, another drug recommended by the WHO – Coartem – is also not getting to patients in the developing worlds of Africa and Asia. ”There is currently a shortage of the drug,” said MMV’s Wang. ‘'(This) is a combination drug containing the potent ingredient artemisinin.”

”The drug is also relatively expensive at 2.40 US dollars per adult treatment. It is 10-30 times the price of chloroquine,” she added.

Yet for anti-malaria campaigners like Sornchai, the lessons learnt from chloroquine remain pivotal as the race for its successor drugs goes ahead. Most important for him was that it was cheap, safe and easy to use.

”Our strategy is to come out with a cheap drug that is simple to take for children, pregnant women and adults,” he said. ”The treatment should cost around one dollar.”

And to overcome the possible rise of another drug-resistant strain of malaria, the researchers at Mahidol University are determined to produce at least one new drug every four to five years.

It is a prescription that Sornchai feels will help meet the goal the WHO set in 1998 when it launched the ‘Roll Back Malaria Campaign’ û to halve the number of people dying from this disease by 2010.