Drug discovery for schistosomiasis: hit and lead compounds identified in a library of known drugs by medium-throughput phenotypic screening.

• Published in: PLoS Neglected Tropical Diseases
• Main Authors: Maha-Hamadien Abdulla, Debbie S Ruelas, Brian Wolff, June Snedecor, Kee-Chong Lim, Fengyun Xu, Adam R Renslo, Janice Williams, James H McKerrow, Conor R Caffrey
• Format: Article in Journal/Newspaper
• Language: English
• Published: Public Library of Science (PLoS) 2009
• Subjects: Arctic medicine. Tropical medicine; RC955-962; Public aspects of medicine; RA1-1270; Arctic
• Online Access: https://doi.org/10.1371/journal.pntd.0000478; https://doaj.org/article/e07426d1155142edb442dafbc6846ea9

Background Praziquantel (PZQ) is the only widely available drug to treat schistosomiasis. Given the potential for drug resistance, it is prudent to search for novel therapeutics. Identification of anti-schistosomal chemicals has traditionally relied on phenotypic (whole organism) screening with adult worms in vitro and/or animal models of disease-tools that limit automation and throughput with modern microtiter plate-formatted compound libraries. Methods A partially automated, three-component phenotypic screen workflow is presented that utilizes at its apex the schistosomular stage of the parasite adapted to a 96-well plate format with a throughput of 640 compounds per month. Hits that arise are subsequently screened in vitro against adult parasites and finally for efficacy in a murine model of disease. Two GO/NO GO criteria filters in the workflow prioritize hit compounds for tests in the animal disease model in accordance with a target drug profile that demands short-course oral therapy. The screen workflow was inaugurated with 2,160 chemically diverse natural and synthetic compounds, of which 821 are drugs already approved for human use. This affords a unique starting point to 'reposition' (re-profile) drugs as anti-schistosomals with potential savings in development timelines and costs. Findings Multiple and dynamic phenotypes could be categorized for schistosomula and adults in vitro, and a diverse set of 'hit' drugs and chemistries were identified, including anti-schistosomals, anthelmintics, antibiotics, and neuromodulators. Of those hits prioritized for tests in the animal disease model, a number of leads were identified, one of which compares reasonably well with PZQ in significantly decreasing worm and egg burdens, and disease-associated pathology. Data arising from the three components of the screen are posted online as a community resource. Conclusions To accelerate the identification of novel anti-schistosomals, we have developed a partially automated screen workflow that interfaces schistosomula ...