Praziquantel

Praziquantel is an anthelmintic effective against flatworms.

TREATMENT OF PULMONICOLA COCHLEOTREMA INFECTION WITH IVERMECTIN-PRAZIQUANTEL COMBINATION IN AN ANTILLEAN MANATEE (TRICHECHUS MANATUS MANATUS).[Pubmed:28363040]

J Zoo Wildl Med. 2017 Mar;48(1):217-219.

The aim of this study was to report the use of an oral combination of ivermectin plus Praziquantel in the treatment of a Pulmonicola cochleotrema in an Antillean manatee ( Trichechus manatus manatus). A female manatee was found exhibiting respiratory changes and the presence of parasites in the nares. Based on clinical manifestations presented by the manatee, a symptomatic therapeutic protocol was employed, which included an anthelmintic treatment using a combination of ivermectin plus Praziquantel. The parasites retrieved were identified as P. cochleotrema. The fourth day after the onset of the therapeutic protocol, the clinical signs declined and on the seventh day posttreatment no clinical signs were observed. This is the first time a therapeutic protocol of ivermectin plus Praziquantel has been used in the treatment of P. cochleotrema in manatees.

Praziquantel for Schistosomiasis: Single-Drug Metabolism Revisited, Mode of Action, and Resistance.[Pubmed:28264841]

Antimicrob Agents Chemother. 2017 Apr 24;61(5). pii: AAC.02582-16.

Schistosomiasis, a major neglected tropical disease, affects more than 250 million people worldwide. Treatment of schistosomiasis has relied on the anthelmintic drug Praziquantel (PZQ) for more than a generation. PZQ is the drug of choice for the treatment of schistosomiasis; it is effective against all major forms of schistosomiasis, although it is less active against juvenile than mature parasites. A pyrazino-isoquinoline derivative, PZQ is not considered to be toxic and generally causes few or transient, mild side effects. Increasingly, mass drug administration targeting populations in sub-Saharan Africa where schistosomiasis is endemic has led to the appearance of reduced efficacy of PZQ, which portends the selection of drug-resistant forms of these pathogens. The synthesis of improved derivatives of PZQ is attracting attention, e.g., in the (i) synthesis of drug analogues, (ii) rational design of pharmacophores, and (iii) discovery of new compounds from large-scale screening programs. This article reviews reports from the 1970s to the present on the metabolism and mechanism of action of PZQ and its derivatives against schistosomes.

Molecular modeling and infrared and Raman spectroscopy of the crystal structure of the chiral antiparasitic drug Praziquantel.[Pubmed:28275906]

J Mol Model. 2017 Apr;23(4):106.

Anthelmintic Praziquantel (PZQ) and its molecular and crystal lattice structures were studied by means of atomistic calculations based on empirical interatomic potentials and quantum mechanical methods (DFT). This chiral drug presents several crystal polymorphs due to the enantiomers (either R or S) or the racemic crystal, and different molecular conformations. The relative configurations of the carbonyl groups in PZQ define these conformations that produce different polymorphs. The polarity of these conformers is quite different and their relative population can vary in media with different polarity. Crystal structures of PZQ were studied by infrared and Raman spectroscopy and their spectroscopical properties were calculated by quantum mechanical methods, assigning many of their bands, and finding a good agreement with experimental data.

Controlling schistosomiasis with praziquantel: How much longer without a viable alternative?[Pubmed:28351414]

Infect Dis Poverty. 2017 Mar 28;6(1):74.

The current approach of morbidity control of schistosomiasis, a helminth disease of poverty with considerable public health and socioeconomic impact, is based on preventive chemotherapy with Praziquantel. There is a pressing need for new drugs against this disease whose control entirely depends on this single drug that has been widely used over the past 40 years. We argue that a broader anthelminthic approach supplementing Praziquantel with new antischistosomals targeting different parasite development stages would not only increase efficacy but also reduce the risk for drug resistance. Repositioning drugs already approved for other diseases provides a shortcut to clinical trials, as it is expected that such drugs rapidly pass the regulatory authorities. The antischistosomal properties of antimalarial drugs (e.g., semisynthetic artemisinins, synthetic trioxolanes, trioxaquines and mefloquine) and of drugs being developed or registered for other purposes (e.g., moxidectin and miltefosin), administered alone or in combination with Praziquantel, have been tested in the laboratory and clinical trials. Another avenue to follow is the continued search for new antischistosomal properties in plants. Here, we summarise recent progress made in schistosomiasis chemotherapy, placing particular emphasis on repositioning of existing drugs against schistosomiasis.