Combined drug therapy effective for kala-azar cure

Bangladeshi researchers have found that a combination of two drugs is “most effective” in treating kala-azar, a debilitating tropical disease that mostly affects the poor.

The findings of the four-year clinical trial conducted in Bangladesh released on Wednesday could change the current kala-azar treatment regimen in the region.

Bangladesh is one of few South-Asian countries where the sand fly-borne disease is prevalent, though its incidence rate has fallen drastically over the years.

Drugs are being used singly to treat patients even in India and Nepal.

The new study now reveals that AmBisome, Miltefosine and Paromomycin work best when combined. Left untreated, kala-azar can be fatal.

Principal investigator Prof Md Ridwanur Rahman of Shaheed Suhrawardhy Medical College in Dhaka, said the currently used single drug AmBisome for treating the ailment had the potential to cause a “severe adverse effect” including death.

“One in 100 patients may die during treatment due to adverse effects. Besides, a patient needs to take it for a month; so in most of the cases poor patients do not complete the course, leaving a scope for developing drug resistance,” he told bdnews24.com.

“So we needed an effective drug for the country,” the professor of medicine said.

They tested the combination on 602 patients and the efficacy rate was as high as over 98 percent.

“The single drug was 91 percent effective,” he said.

“Even treatment cost comes down, as fewer doses are needed,” he said.
The affordability would encourage the completion of the course and prevent drug resistance, he said. “This is very urgent for us since we don’t have any new drug (for treating kala-azar) in the pipeline.”

A long wait ends

Kala-azar treatment was too expensive for the poor, prompting the government to offer free treatment, including drugs supplied by WHO.

This combination will lower the cost of the governments to buy those drugs, if needed.

The chief investigator hoped that the combination would find a place in the kala-azar elimination programme shortly.

“In fact the Regional Technical Advisory Group (RTAG) was waiting for the findings of this research.

“Now they have options. They can pick any of them and suggest a new plan”.

The advisory group works in line with the WHO agreement that Bangladesh, India, Nepal, Bhutan and Thailand would eliminate kala-azar by 2020.

The elimination of kala-azar means reducing the number of cases to a level where it is no longer a public health problem.

The target is to cut the incidence to one per 10,000 people annually at the district or sub-district level.

Health Minister Mohammed Nasim who was present at the study releasing ceremony congratulated the researchers, saying it would show a new way to fight kala-azar.

“This will help in eliminating the disease effectively,” he said.

Sustainability challenge

The sand-fly that causes kala-azar breeds in moist soil, caves, cracks in mud walls and rodent burrows. The disease is closely linked with malnutrition, poor housing, and illiteracy.

Prof MA Faiz, who is a member of the board of Drugs for Neglected Diseases Initiative that supported the study, said kala-azar elimination was possible, but sustaining the success would be a challenge.

“It’s not a health issue only when you talk about total elimination,” he said.

“You have to mobilise the community so that they keep the environment clean,” he said.

Bangladesh is one of the few countries in the world where six vector-borne diseases are present.

“In fact those are linked with one another if you talk about vector control or management. So it needs holistic approach,” he said.

In the 1960s, due to massive DDT spraying, kala-azar had almost disappeared, but showed up again in the 1980s.

“It needs a holistic approach to sustain the elimination”, Prof Faiz said.

The government did not record any kala-azar deaths last year, though the disease was prevalent in 25 districts.

Different medical colleges in the kala-azar prone areas were involved in the clinical trial.