Our work

River blindness

We’ve completed the development of a new treatment for this debilitating disease


What is river blindness?

River blindness (onchocerciasis) is a disease caused by the parasitic worm Onchocerca volvulus, which is transmitted to humans through repeated bites from infected black flies. The resulting infection can lead to visual impairment and even blindness, severe itching, and debilitating and disfiguring effects on the skin, such as nodules.


Why are we targeting this disease?


people are at risk of infection


African countries are where the majority of infected people live


people estimated to have vision loss due to the disease


Transmission stages of Onchocerca volvulus


Moxidectin for river blindness

The current standard treatment for river blindness is an anti-parasitic medicine called ivermectin. It has been generously donated by Merck & Co., Inc. (MSD outside of the United States) and distributed to areas in which the disease is endemic for over 30 years. But there are many areas where the prevalence of river blindness remains high, even with annual community-directed treatment with ivermectin. 

Moxidectin is from the same class of drugs as ivermectin but due to its substantially longer half-life in the body, it suppresses the disease-causing microfilariae in more patients, more extensively and for longer. Moxidectin has a similar safety profile as ivermectin with both medicines well tolerated. The most common adverse events reported in Phase 2 and 3 studies were transient and self-limiting, generally occurring and resolving within the first week of treatment. Modelling studies suggest that moxidectin has the potential to significantly reduce time to elimination of this disease.

In 2018, we received US FDA approval for moxidectin for river blindness for people aged 12 years and older. We are now generating the additional data required to carry out community-directed treatment in endemic areas, through targeting World Health Organization (WHO) endorsement for use in river blindness treatment programs. We are also working on local regulatory approval in African countries and the evaluation of pilot implementation studies in several river blindness-endemic countries.

See Frequently Asked Questions on Moxidectin for Onchocerciasis: Click here

We are conducting a cutting-edge moxidectin pharmacokinetic modelling program in breastfeeding and pregnant women, to better estimate the impact of treating this group with moxidectin, as well as modelling to determine how moxidectin could reduce time to elimination of this disease. 

Paediatric formulation studies are also underway to determine the best format for use in children under four years of age and others unable to swallow tablets.

Finally, we continue to explore the most effective ways of manufacturing and distributing moxidectin, to accelerate the elimination of river blindness.

Photo acknowledgement: Gbonjeima, Sierra Leone. Olivier Asselin, 2012. 


Moxidectin project websites

Moxidectin icon showing 3 blue tablets

Moxidectin for accelerating onchocerciasis elimination

A paediatric dose-finding study, a phase 3b trial comparing efficacy and safety of annual and biannual moxidectin or ivermectin treatment and mathematical modelling of moxidectin and ivermectin based elimination strategies to support country policy decisions.

Moxidectin icon showing 3 blue tablets

Treatment for all

Developing a paediatric formulation moxidectin for neglected infectious diseases.


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Take a look at the research and development work

Disease areas

Primarily affecting the lungs, tuberculosis remains the leading cause of infectious death worldwide.


A debilitating and disfiguring disease found in 31 African countries and beyond.

River blindness

An infectious skin condition affecting more than 200 million people at any one time.


A painful and debilitating disease of the lymph system affecting over 50 million people at any one time.

Lymphatic filariasis

A soil-transmitted infection affecting up to 100 million people, particularly children.


A chronic infectious disease which may cause skin lesions and nerve damage found in 127 countries.


Among the most common of all infections with an estimated 1.5 billion people infected worldwide.

Soil-transmitted helminth infections