A clinical trial is being launched in three African countries of a drug that could eliminate onchocerciasis, or river blindness, one of the leading infectious causes of blindness across Africa. The drug, moxidectin, is being investigated for its potential to kill or sterilize the adult worms of Onchocerca volvulus, which cause onchocerciasis.
"This is a devastating illness that has plagued 30 African countries for centuries, in particular the populations in the most remote areas 'beyond the end of the road'," says Dr Uche Amazigo, Director of the African Programme for Onchocerciasis Control (APOC). "Over 100 million people are at risk of infection with onchocerciasis in Africa and a few small areas in the Americas and Yemen."
Onchocerciasis is 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.
The development of moxidectin for onchocerciasis is being conducted through a collaboration of the Special Programme for Research and Training in Tropical Diseases (TDR), which is administered by WHO, with Wyeth Pharmaceuticals. The work ranges from the development of a formulation for human use and initial studies in healthy volunteers, to clinical studies and community studies in Africa.
TDR is building the capacity and managing the clinical trials in Africa. If the development is successful and results in a positive scientific opinion from the European Medicines Evaluation Agency, Wyeth with the assistance of WHO will request approval by regulatory authorities in the countries where onchocerciasis is endemic.
Promising data
Dr Henrietta Ukwu, Vice President of Wyeth Pharmaceuticals, says, "Wyeth is committed to improving access to innovative drugs and biologics around the globe including in the developing world. The moxidectin data have been promising so far, and as the programme moves into larger phase III studies, we are hopeful that moxidectin will constitute a significant advance against this devastating disease.”
TDR will be working with African investigators and institutions for the trial, enrolling 1500 people at four sites in Ghana, Liberia and the Democratic Republic of the Congo. Preparation has been ongoing since 2007 and include building a clinical research centre in Lofa County in Liberia and in Nord-Kivu in the Democratic Republic of the Congo. Buildings not used since the war in Ituri in the Democratic Republic of the Congo have been renovated. All centres have been provided with necessary equipment and the research teams trained on how to conduct the trial according to international standards.