Current and prospective chemotherapy options for schistosomiasis

Introduction: Schistosomiasis remains one of the most insidious and serious of the tropical parasitic diseases. There is currently no anti-schistosome vaccine, but praziquantel (PZQ), the only drug currently used for treatment, is cheap, highly effective against all species of schistosomes, and has limited side effects. However, the emergence of PZQ drug resistance remains a concern and represents a significant threat to public health. Areas covered: This review discusses potential mechanisms of PZQ action and how molecular changes in schistosome parasites may lead to resistance. We emphasize new molecular and cellular approaches to characterize and quantitate schistosome responses to both current and newly developed antischistosomals. Further, we discuss the identification of new drug targets impacting on key biological functions in schistosome parasites. These include the apoptosis pathway, kinase signaling and key components of biological significance such as thioredoxin, glutathione reductase and septins.Expert opinion: The identification of critical molecular targets in schistosomes leading to the development of new drugs is urgently needed for the future treatment of schistosomiasis. An additional strategy for consideration is to increase and broaden the efficacy of PZQ, which may involve combination therapy with new antischistosomals so as to target multiple molecular components of schistosomes.