Clinical trials

Sickle cell anemia (SCA) is among the world's most common and devastating blood disorders, affecting more than 300,000 newborns per year. Most infants with SCA are born in the low-resource settings of sub- Saharan Africa, where an estimated 50-90% will die before 5 years of age due to lack of early diagnosis and appropriate care. Hydroxyurea is a safe and effective once-daily oral medication that has become the standard of care for the treatment of children with SCA in high-resource settings. There is now a growing body of evidence to support the safety and clinical benefits of hydroxyurea for the treatment of SCA in sub-Saharan Africa. The requirement for frequent laboratory monitoring, uncertainties about appropriate, most effective dosing, and the concern for hematologic laboratory toxicities, however, will continue to limit widespread hydroxyurea utilization and real-world effectiveness. The investigators have recently developed and prospectively evaluated an individualized, pharmacokinetics-guided hydroxyurea dosing strategy for children with SCA that has demonstrated optimal clinical and laboratory benefits with minimal toxicity. In this research study, the investigators aim to extend this precision medicine approach to Africa.

This clinical trial compares two treatments - ivermectin and moxidectin - to learn which is better at reducing the proportion of people with onchocerciasis (river blindness) when given through mass drug administration (MDA) in Angola. Both drugs are approved by the United States Food and Drug Administration (FDA) to treat this disease. The study also explores how these treatments affect other infections common in the region, including intestinal worms (soil-transmitted helminths) and scabies. The trial aims to answer the following key questions: * How do moxidectin and ivermectin compare in reducing the prevalence (how common the disease is) and intensity (amount of parasites per person) of onchocerciasis in the community? * Do the treatments differ in their effect on the prevalence and intensity of soil-transmitted helminths and the prevalence of scabies? * Does moxidectin reduce transmission of onchocerciasis more effectively than ivermectin, based on genetic testing of parasites in people and lab testing of the blackflies that carry the infection? * How many more years of treatment would be needed to reach elimination with each drug, based on mathematical disease modelling? * How do communities feel about receiving moxidectin versus ivermectin, and what factors help or make it harder to carry out MDA programs with moxidectin versus ivermectin? The study takes place in Bié Province, Angola, and involves 20 groups of villages randomly assigned to receive either moxidectin or ivermectin once a year for four years. Prior to every round of MDA, researchers will collect skin, stool and blood samples from a sample of the people living in the study area. We believe the results will help guide global policy on the use of moxidectin in efforts to eliminate onchocerciasis and control related diseases.

This study will investigate the role of genetic modifiers in hemoglobinopathies through a large-scale, multi-ethnic genome-wide association study (GWAS).