Interest in repurposing available antibiotics for the treatment of drug-resistant staphylococcal infections has led to evaluation of two anthelmintic drugs, niclosamide and oxyclozanide.
When tested in vitro against multi-drug-resistant strains of Staphylococcus aureus, niclosamide was found to be bacteriostatic whereas oxyclozanide was bacteriocidal. Interestingly, oxyclozanide — a veterinary drug — was found to attack the cell membrane rather than intracellular pathways, making drug resistance less likely to develop.
“Further studies are needed to study the exact mode of action of these drugs and their pharmacokinetic and pharmacodynamics profiles,” the authors write in PLoS ONE
(online, 21 April 2015). “Since niclosamide is FDA-approved and all of the salicylanilide anthelmintic drugs are already out of patent, they are attractive candidates for drug repurposing.”
 Rajamuthiah R, Fuchs BB, Conery AL et al. Repurposing salicylanilide anthelmintic drugs to combat drug resistant Staphylococcus aureus. PLoS ONE 2015;10(4):e0124595. doi:10.1371/journal.pone.0124595.