{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,5,15]],"date-time":"2026-05-15T17:00:40Z","timestamp":1778864440124,"version":"3.51.4"},"reference-count":40,"publisher":"MDPI AG","issue":"2","license":[{"start":{"date-parts":[[2024,1,31]],"date-time":"2024-01-31T00:00:00Z","timestamp":1706659200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Drugs for Neglected Diseases initiative, Geneva","award":["EXC2151 390873048"],"award-info":[{"award-number":["EXC2151 390873048"]}]},{"name":"Drugs for Neglected Diseases initiative, Geneva","award":["TTU 09.701"],"award-info":[{"award-number":["TTU 09.701"]}]},{"name":"Germany\u2019s Excellence Strategy","award":["EXC2151 390873048"],"award-info":[{"award-number":["EXC2151 390873048"]}]},{"name":"Germany\u2019s Excellence Strategy","award":["TTU 09.701"],"award-info":[{"award-number":["TTU 09.701"]}]},{"name":"German Center for Infection Research","award":["EXC2151 390873048"],"award-info":[{"award-number":["EXC2151 390873048"]}]},{"name":"German Center for Infection Research","award":["TTU 09.701"],"award-info":[{"award-number":["TTU 09.701"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Pharmaceutics"],"abstract":"<jats:p>Onchocerciasis treatment and control relies mainly on the use of ivermectin which has high activity against the microfilarial stage of Onchocerca volvulus but limited activity against the long-lived, tissue dwelling adult nematodes. As this neglected tropical disease has now been targeted for elimination, there is an urgent need for new drugs to combat these parasites, ideally with macrofilaricidal activity. In this study, we have examined the anti-Onchocerca activity of a range of existing FDA-approved drugs with a view to repurposing, which can lead to rapid and relatively inexpensive development. From the Pharmakon-1600 library, 106 drugs were selected and tested against O. gutturosa adult male parasites using a concentration of 1.25 \u00d7 10\u22125 M in an in vitro 5-day standard assay to assess motility and viability (using MTT\/formazan colorimetry). The findings revealed that 44 drugs produced marginal\/moderate activity (50\u201399% motility and\/or MTT reductions) including cefuroxime sodium, methenamine, primaquine phosphate and rivastigmine tartrate, while 23 drugs produced good activity (100% motility reductions and significant MTT reductions), including atovaquone, isradipine, losartan, rifaximin, cefaclor and pyrantel pamoate. Although this study represents only a first step, some of the identified hits indicate there are potential anti-Onchocerca drug candidates worthy of further investigation.<\/jats:p>","DOI":"10.3390\/pharmaceutics16020210","type":"journal-article","created":{"date-parts":[[2024,1,31]],"date-time":"2024-01-31T09:41:59Z","timestamp":1706694119000},"page":"210","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":4,"title":["Onchocerciasis Drug Discovery: In Vitro Evaluation of FDA-Approved Drugs against Onchocerca gutturosa in Gambia"],"prefix":"10.3390","volume":"16","author":[{"given":"Suzanne","family":"Gokool","sequence":"first","affiliation":[{"name":"Tropical Parasitic Diseases Unit, Northwick Park Institute for Medical Research, Watford Road, Harrow, London HA1 3UJ, UK"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Simon","family":"Townson","sequence":"additional","affiliation":[{"name":"Tropical Parasitic Diseases Unit, Northwick Park Institute for Medical Research, Watford Road, Harrow, London HA1 3UJ, UK"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Andrew","family":"Freeman","sequence":"additional","affiliation":[{"name":"Tropical Parasitic Diseases Unit, Northwick Park Institute for Medical Research, Watford Road, Harrow, London HA1 3UJ, UK"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Jadzia","family":"Siemienski-Kleyn","sequence":"additional","affiliation":[{"name":"Tropical Parasitic Diseases Unit, Northwick Park Institute for Medical Research, Watford Road, Harrow, London HA1 3UJ, UK"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Jakub","family":"Zubrzycki","sequence":"additional","affiliation":[{"name":"Tropical Parasitic Diseases Unit, Northwick Park Institute for Medical Research, Watford Road, Harrow, London HA1 3UJ, UK"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Senyo","family":"Tagboto","sequence":"additional","affiliation":[{"name":"Tropical Parasitic Diseases Unit, Northwick Park Institute for Medical Research, Watford Road, Harrow, London HA1 3UJ, UK"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8885-418X","authenticated-orcid":false,"given":"Marc P.","family":"H\u00fcbner","sequence":"additional","affiliation":[{"name":"Institute for Medical Microbiology, Immunology and Parasitology, University Hospital Bonn, Venusberg-Campus 1, 53127 Bonn, Germany"},{"name":"German Center for Infection Research (DZIF), Partner Site Bonn-Cologne, 53127 Bonn, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4242-9289","authenticated-orcid":false,"given":"Ivan","family":"Scandale","sequence":"additional","affiliation":[{"name":"Drugs for Neglected Diseases Initiative, 1202 Geneva, Switzerland"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2024,1,31]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"105677","DOI":"10.1016\/j.actatropica.2020.105677","article-title":"Onchocerciasis (river blindness)\u2014More than a century of research and control","volume":"218","author":"Brattig","year":"2021","journal-title":"Acta Trop."},{"key":"ref_2","unstructured":"WHO (2023, October 15). 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