Advances in Drug Discovery against Neglected Tropical Diseases: Human African and American Trypanosomiasis.

Human African and American trypanosomiasis are the vector-borne parasitic diseases that have killed millions of people early, and many people are still suffering from these neglected diseases. The causative agents of these infections are parasitic protozoans of the genus Trypanosoma. Current treatment regimens against these endemic diseases have several limitations in terms of safety, efficacy, route of administration, and some of them have lost efficacy due to the emergence of resistance in their respective parasites. In this review, the most promising compounds identified by different strategies of drug development against these neglected diseases, including target-based approach, the phenotypic high-throughput screening, the drug repurposing approach, and combination therapy, are emphasized. The potent heterocyclic compounds currently undergoing pre-clinical or clinical studies have also been assessed to ascertain an effective class of organic compounds having significant therapeutic potential against these tropical diseases. The molecular hybridization of outlined motifs may result in more active compounds and circumvent the development of resistance by specific targets in the future.