A snapshot of selected neglected tropical disease research using the World Health Organization International Clinical...

Knowledge of clinical study methodology and location can inform researchers, clinicians, funders, and policymakers of the gaps which exist in a disease's evidence landscape, thereby conferring guidance for appropriate resource allocation. This study summarises registered studies for selected neglected tropical diseases (NTDs) and identifies evidence gaps.

The International Clinical Trials Registry Platform (ICTRP) was searched in September 2023 to extract 315 clinical study registrations submitted between January 1999 and September 2023 on Chagas disease, schistosomiasis, soil-transmitted helminthiases, and visceral leishmaniasis. Data were standardised before a descriptive analysis was performed on study location, inclusion age range, study design, phase, and population access to studies.

Registered studies were partially aligned to the geographical distribution of disease burden; countries in which the highest number of studies were registered often face great burden, though there were several endemic countries with few or no studies. The number of registered studies increased over time in the period covered by the review, with 51-62% of studies across the 4 diseases conducted in 2014-23 period, as opposed to 42%-49% in the preceding 15 years. Only 12-17% of studies were multi-country studies across the 4 NTDs. 14% of Chagas disease studies included children under the age of 16 years (much lower than other NTDs) and only 2 studies (2%) exclusively studied under 16s.

These findings highlight areas of research for these diseases which have been neglected between 1999-2023, indicating need for further research to fill these gaps and aid progress towards the World Health Organization's roadmaps to elimination of NTDs by 2030.