Authors
P Panwar2; M Abubakker2; K K Burusco1; R Bryce1; N Nirmalan2; 1 University of Manchester, UK; 2 University of Salford, UK Discussion
Drug resistance has emerged towards all antimalarials in use including the Artemisinin-based combination therapies. There is a pressing need for novel anti-malarial treatments but long development timelines cripple the process of drug discovery. An alternative to de novo drug design is offered by drug repositioning to help reduce the long timescale involved in bringing a drug to market. Natural products have been a reliable source of anti-malarial treatments. Emetine dihydrochloride, an anti-amoebic compound, has been identified to be a potent inhibitor of the multi-drug resistant strain K1 of Plasmodium falciparum (IC50: 47nM) and shows ideal pharmacokinetic matching and synergy with atovaquone. The use of emetine has been prevented by its emetic and cardiotoxic effects. However, synthetic analogues of emetine hydrochloride have been claimed to be less cardiotoxic than the parent compound. Using in-silico modelling methods, synthetic emetine analogues were found to have the potential for retaining the anti-malarial activity. The results were verified experimentally. Emetine and its analogues were found to have a multi-modal mechanism of action. A huge investment of time and resources are needed for high throughput screening and in-silico virtual screening provides an inexpensive alternative to filter through large libraries of compounds. Virtual screening of FDA approved library of drugs was carried out to identify synergies and propose anti-malarial combination therapy between these drugs and synthetic emetine analogues. 
