WHO tests river blindness drug

2009-07-03 07:54

Geneva - The World Health Organisation said on Wednesday it was launching a clinical trial for a drug that could halve the treatment period for river blindness, a disease that threatens 100 million people mostly in Africa.

The phase three trial of the drug moxidectin, in collaboration with Wyeth Pharmaceuticals, would involve 1 500 people in Ghana, Liberia and the Democratic Republic of Congo, said the WHO.

Also called onchocerciasis, river blindness is caused by a parasitic worm whose larvae are transmitted by the bite of the black fly, which breeds by fast-flowing streams.

The larvae migrate under the skin, where they mature into adult worms that produce more eggs.

The eggs then mature into a threadlike state called microfilariae, before developing into larvae.

The microfilariae are especially dangerous as they migrate to the surface of the cornea, causing eye infection and, eventually, blindness.

The clinical trial would examine moxidectin's potential to kill or sterilise adult worms.

River blindness is now being controlled by Merck's ivermectin.

However, the drug kills only the larvae but not the adult worms. As a result, treatment for the disease can last for up to 14 years.

In comparison, if moxidectin proves to be able to neutralise adult worms, it can shorten the treatment period to six years, according to the WHO.

If the trial proves to be positive, the WHO said it would help Wyeth to seek approval for usage in the countries where the disease is endemic.

- SAPA