GENEVA (AFP)--The World Health Organization said 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 (WYE), would involve 1,500 people in
Ghana, Liberia and 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 & Co.'s
(MRK) 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.