title: Repurposing of approved drugs from the human pharmacopoeia to target Wolbachia endosymbionts of onchocerciasis and lymphatic filariasis.
abstract: Lymphatic filariasis and onchocerciasis are debilitating diseases caused by parasitic filarial nematodes infecting around 150 million people throughout the tropics with more than 1.5 billion at risk. As with other neglected tropical diseases, classical drug-discovery and development is lacking and a 50 year programme of macrofilaricidal discovery failed to deliver a drug which can be used as a public health tool. Recently, antibiotic targeting of filarial Wolbachia, an essential bacterial symbiont, has provided a novel drug treatment for filariasis with macrofilaricidal activity, although the current gold-standard, doxycycline, is unsuitable for use in mass drug administration (MDA). The anti-Wolbachia (A·WOL) Consortium aims to identify novel anti-Wolbachia drugs, compounds or combinations that are suitable for use in MDA. Development of a Wolbachia cell-based assay has enabled the screening of the approved human drug-pharmacopoeia (∼2600 drugs) for a potential repurposing. This screening strategy has revealed that approved drugs from various classes show significant bacterial load reduction equal to or superior to the gold-standard doxycycline, with 69 orally available hits from different drug categories being identified. Based on our defined hit criteria, 15 compounds were then selectively screened in a Litomosoides sigmodontis mouse model, 4 of which were active. These came from the tetracycline, fluoroquinolone and rifamycin classes. This strategy of repurposing approved drugs is a promising development in the goal of finding a novel treatment against filariasis and could also be a strategy applicable for other neglected tropical diseases.
authors.affiliation: Filariasis Research Group, Department of Parasitology, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool L3 5QA, UK.
authors.forename: Kelly L
authors.initials: KL
authors.lastname: Johnston
authors.affiliation: Filariasis Research Group, Department of Parasitology, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool L3 5QA, UK.
authors.forename: Louise
authors.initials: L
authors.lastname: Ford
authors.affiliation: CombinatoRx-Singapore Ptd Ltd, 11 Biopolis Way, 138667 Singapore, Singapore.
authors.forename: Indira
authors.initials: I
authors.lastname: Umareddy
authors.affiliation: Tropical Parasitic Diseases Unit, Northwick Park Institute for Medical Research, Watford Road, Harrow, Middlesex HA1 3UJ, UK.
authors.forename: Simon
authors.initials: S
authors.lastname: Townson
authors.affiliation: Institute of Medical Microbiology, Immunology & Parasitology, University Hospital of Bonn, Sigmund Freud Strasse 25, 53105 Bonn, Germany.
authors.forename: Sabine
authors.initials: S
authors.lastname: Specht
authors.affiliation: Institute of Medical Microbiology, Immunology & Parasitology, University Hospital of Bonn, Sigmund Freud Strasse 25, 53105 Bonn, Germany.
authors.forename: Kenneth
authors.initials: K
authors.lastname: Pfarr
authors.affiliation: Institute of Medical Microbiology, Immunology & Parasitology, University Hospital of Bonn, Sigmund Freud Strasse 25, 53105 Bonn, Germany.
authors.forename: Achim
authors.initials: A
authors.lastname: Hoerauf
authors.affiliation: CombinatoRx-Singapore Ptd Ltd, 11 Biopolis Way, 138667 Singapore, Singapore ; Institut Pasteur Shanghai, Chinese Academy of Sciences, 320 Yueyang Road, 200031 Shanghai, People's Republic of China.
authors.forename: Ralf
authors.initials: R
authors.lastname: Altmeyer
authors.affiliation: Filariasis Research Group, Department of Parasitology, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool L3 5QA, UK.
authors.forename: Mark J
authors.initials: MJ
authors.lastname: Taylor
keywords: Anti-Wolbachia Consortium (A·WOL); Drug discovery; Filariasis; Library screening; Pharmacopoeia; Wolbachia