Trends in Parasitology
Research updateNew policies for using anthelmintics in high risk groups
Section snippets
Experimental animal studies
Following toxicology studies in 1989, it was concluded that, by contrast to most other anthelmintic drugs, PZQ had no known detrimental effects in experimental animals, when given either acutely or chronically, and in doses well above those routinely administered to humans. Of specific importance, reproductive toxicity was studied in rats, rabbits and Syrian hamsters without negative effects [2]. In fact, drug treatment is allowed in breeding animals and lactating cows. When the patent on PZQ
Human toxicology
Since the release of PZQ, human toxicology data have been collected by the US Food and Drug Administration (Rockville, MA, USA) and Bayer. No cases have been uncovered which suggest adverse birth outcomes associated with PZQ use. Importantly, several pregnant women have been intentionally given PZQ for the treatment of cysticercosis – a treatment that uses the equivalent of the highest single dose of PZQ, repeated for 10–14 consecutive days, with no apparent adverse outcomes. Moreover, during
Risk–benefit analysis
The pivotal point of this conference rested on an analysis of the benefits of treatment. The argument to withhold PZQ until after pregnancy has always focused on the possibility of toxicity, rather than the detrimental effects of the untreated disease on the mother and child. If the morbidity induced by untreated infections is examined, three compelling arguments emerge.
First, we now know that schistosomiasis-induced organ damage can progress over relatively short periods of time (<9 months).
Conclusion
After two decades of clinical experience with these drugs and significant new experimental data, the conference recommended the following:
- 1.
Pregnant and lactating women are at least as susceptible as anyone else to end-organ morbidity due to schistosomiasis. Moreover, the fact that pathology can develop more rapidly in pregnant women than previously thought means that treatment delays are more likely to result in even more serious outcomes. Therefore, all infected pregnant and lactating women
Acknowledgements
We acknowledge Dirk Engels, Antonio Montresor and Lorenzo Savioli (Parasitic Diseases and Vector Control Unit, Dept of Communicable Diseases, Control, Prevention and Eradication, WHO, Geneva, Switzerland) for their invaluable contributions to this article and for organizing the meeting. We also acknowledge Anthony Dayan and Peter Folb for their major contribution to the outcome of the meeting.
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Efficacy and safety of praziquantel for the treatment of human schistosomiasis during pregnancy: A phase 2, randomised, double-blind, placebo-controlled trial
2016, The Lancet Infectious DiseasesCitation Excerpt :Its class B designation is based on numerous animal studies supporting its safety,3,4 but there is a lack of well controlled trials during human pregnancy. In 2002, a WHO report recommended that all schistosomiasis-infected pregnant and lactating women be considered high-risk groups and be offered treatment with praziquantel individually or during treatment campaigns.5–7 This recommendation was reissued in 2006 as part of the WHO guidelines for preventative chemotherapy for helminthiasis,2 in which it was recommended that pregnant and lactating women be included in mass drug administration campaigns.
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