title: Efficacy of praziquantel against Schistosoma mekongi and Opisthorchis viverrini: a randomized, single-blinded dose-comparison trial.
abstract: BACKGROUND
  Schistosomiasis and opisthorchiasis are of public health importance in Southeast Asia. Praziquantel (PZQ) is the drug of choice for morbidity control but few dose comparisons have been made.
  
  
  METHODS
  Ninety-three schoolchildren were enrolled in an area of Lao PDR where Schistosoma mekongi and Opisthorchis viverrini coexist for a PZQ dose-comparison trial. Prevalence and intensity of infections were determined by a rigorous diagnostic effort (3 stool specimens, each examined with triplicate Kato-Katz) before and 28-30 days after treatment. Ninety children with full baseline data were randomized to receive PZQ: the 40 mg/kg standard single dose (n = 45) or a 75 mg/kg total dose (50 mg/kg+25 mg/kg, 4 hours apart; n = 45). Adverse events were assessed at 3 and 24 hours posttreatment.
  
  
  RESULTS
  Baseline infection prevalence of S. mekongi and O. viverrini were 87.8% and 98.9%, respectively. S. mekongi cure rates were 75.0% (95% confidence interval (CI): 56.6-88.5%) and 80.8% (95% CI: 60.6-93.4%) for 40 mg/kg and 75 mg/kg PZQ, respectively (P = 0.60). O. viverrini cure rates were significantly different at 71.4% (95% CI: 53.4-84.4%) and 96.6% (95% CI: not defined), respectively (P = 0.009). Egg reduction rates (ERRs) against O. viverrini were very high for both doses (>99%), but slightly lower for S. mekongi at 40 mg/kg (96.4% vs. 98.1%) and not influenced by increasing diagnostic effort. O. viverrini cure rates would have been overestimated and no statistical difference between doses found if efficacy was based on a minimum sampling effort (single Kato-Katz before and after treatment). Adverse events were common (96%), mainly mild with no significant differences between the two treatment groups.
  
  
  CONCLUSIONS
  Cure rate from the 75 mg/kg PZQ dose was more efficacious than 40 mg/kg against O. viverrini but not against S. mekongi infections, while ERRs were similar for both doses.
  
  
  BACKGROUND
  Controlled-Trials.com ISRCTN57714676.
authors: Laboratory of Parasitology, University of Neuchâtel, Neuchâtel, Switzerland.
authors: Leonore
authors: L
authors: Lovis
authors: Tippi K
authors: TK
authors: Mak
authors: Khampheng
authors: K
authors: Phongluxa
authors: Phonepasong
authors: P
authors: Ayé Soukhathammavong
authors: Youthanavanh
authors: Y
authors: Vonghachack
authors: Jennifer
authors: J
authors: Keiser
authors: Penelope
authors: P
authors: Vounatsou
authors: Marcel
authors: M
authors: Tanner
authors: Christoph
authors: C
authors: Hatz
authors: Jürg
authors: J
authors: Utzinger
authors: Peter
authors: P
authors: Odermatt
authors: Kongsap
authors: K
authors: Akkhavong
mesh_terms: D000293:Adolescent; D000818:Animals; D000871:Anthelmintics / Q000008:administration & dosage* / Q000494:pharmacology; D002648:Child; D005260:Female; D006801:Humans; D007812:Laos; D008297:Male; D009889:Opisthorchiasis / Q000188:drug therapy*; D009891:Opisthorchis / Q000187:drug effects; D011223:Praziquantel / Q000008:administration & dosage* / Q000494:pharmacology; D012547:Schistosoma / Q000187:drug effects; D012552:Schistosomiasis / Q000188:drug therapy*; D016896:Treatment Outcome
chemical_list: D000871:Anthelmintics; D011223:Praziquantel