Kick-off Meeting for STOP, a Project that Seeks to Interrupt the Transmission of Intestinal Parasites

The first meeting of the STOP project, funded by the EDCTP and coordinated by ISGlobal – an institution supported by the “la Caixa” Foundation -, was held in Barcelona on October 10 and 11. The project consortium, comprised by eight European and African institutions, including a pharmaceutical company, will assess whether an ivermectin/albendazole coformulation is safe and more effective than albendazole alone in treating different intestinal worms, and in eventually stopping their transmission.   

Soil-transmitted helminths (Ascaris, Trichuris, Hookworm and Strongyloides) particularly affect children that live in tropical regions with poor hygiene and sanitation conditions and lead to malnutrition and impaired physical and cognitive development. To control soil-transmitted helminthiasis (STH), the WHO recommends massive administration to pre-school and schoolchildren of the anthelmintic drug albendazole. The drug is safe, but its efficacy against Trichuris has declined to less than 30%, and is practically null against Strongyloides. Furthermore, there is a risk of emerging resistance against the drug.

“This project addresses two pitfalls in the current strategy: albendazole’s suboptimal efficacy, and the risk of developing resistance to the drug,” explains the project coordinator Jose Muñoz, ISGlobal researcher and Head of Tropical Medicine at Hospital Clinic. The STOP consortium proposes adding ivermectin to the treatment in order to increase the efficacy against the different types of parasitic worms and reduce the possibility of resistance by using two different drugs. “One of the project’s strengths is that it incorporates veterinarians, who have worked for years on resistance to anthelminthic drugs used in animals,” adds Muñoz.   

The central pillar of the four-year project is a clinical trial in three African countries with moderate to high prevalence of these helminthic diseases: Kenya, Mozambique and Ethiopia. The trial will include more than 2,000 schoolchildren and will compare the efficacy of albendazole alone versus a co-formulation of albendazole and ivermectin at a fixed dose. The research team will use molecular techniques that are more sensitive than microscopy to detect the presence in stool of eggs from the different worms before and after the treatment. Molecular techniques will also be used to monitor levels of genes related to drug resistance. The project also aims to strengthen capacities and networking in the countries where the clinical trial will be performed.

“If the trial results are positive, we hope to obtain a marketing authorization for the new formulation and help authorities and health organisations find new strategies for STH control,” explains project manager Marc Fernández. This new approach could have a huge impact on reducing the global burden and transmission of this neglected disease and thereby contribute to the achievement of the Sustainable Development Goals,” concludes Muñoz.

The STOP consortium

The consortium partners are: ISGlobal, Leiden University Medical Center LUMC, Netherlands) Bahir Dar University (Ethiopia), the London School of Hygiene and Tropical Medicine (LSHTM), Liconsa laboratories (Spain), the Kenya Medical Research Institute (KEMRI), the Universidad de León (Spain), and the Manhiça Health Research Center (CISM, Mozambique).