UN agency announces start of clinical trial for river blindness drug

1 July - The United Nations health agency today announced the launch of a clinical trial in three African countries for a drug that could help eliminate the debilitating illness commonly known as river blindness, which threatens over 100 million people across the continent.

The development of the drug, moxidectin, is being conducted through a collaboration of the Special Programme for Research and Training in Tropical Diseases, which is executed by the World Health Organization (WHO/TDR), and Wyeth Pharmaceuticals.

Moxidectin is being investigated for its potential to kill or sterilize the adult worms of Onchocerca volvulus which cause onchocerciasis – also called river blindness because the black fly which transmits the disease breeds in fast flowing rivers, and blindness is the most incapacitating symptom of the disease which also causes debilitating skin disease.

Currently, river blindness is controlled by ivermectin, which has contributed to significantly controlling the disease in endemic countries.

But ivermectin kills the O. volvulus larvae and not the adult worms, which means that annual treatments for an extended period of time, at least 11 to 14 years, are required to ensure disease control.

If moxidectin kills not only the larvae but also sterilizes or kills the adult worms, it has the potential to interrupt the disease transmission cycle within around six annual rounds of treatment, according to WHO.

The clinical trial will take place over the next two and a half years and involves 1,500 people at four sites in Ghana, Liberia and the Democratic Republic of the Congo (DRC).