Current status of opisthorchiasis therapy: praziquantel and plant-derived compounds

This lecture examines contemporary therapeutic strategies for opisthorchiasis, focusing on infections caused by the liver fluke Opisthorchis felineus, endemic to Western Siberia. While praziquantel remains the first-line treatment, its clinical utility is constrained by several factors, including lack of efficacy against juvenile parasite forms and emerging drug resistance. The discussion explores alternative pharmacological approaches, encompassing novel synthetic agents, combination therapies, and compounds targeting parasite-specific metabolic pathways. Special attention is given to plant-derived bioactive substances with experimentally confirmed anti-opisthorchiasis activity, including curcumin, Thunbergia laurifolia and Allium sativum extracts, and xanthohumol. These phytochemicals demonstrate dual therapeutic potential: direct antiparasitic effects and modulation of infection-associated pathophysiological processes, such as oxidative/nitrosative stress attenuation, inflammatory response suppression, and hepatobiliary fibrosis progression delay. A synergistic treatment paradigm combining praziquantel’s anthelmintic properties with the pleiotropic effects of plant-based antioxidants and anti-inflammatory compounds shows particular promise. This strategy may improve parasite clearance rates, reduce treatment-related adverse events, and prevent chronic complications. Further investigation is warranted to refine combination protocols, develop targeted delivery systems, and identify next-generation anthelmintic compounds capable of addressing the limitations of current synthetic therapies.

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