52 trials with 10,269 participants were included in a Cochrane review .
Praziquantel 40 mg/kg compared to placebo reduced parasitological treatment failure at one month post-treatment (RR 3.13, 95% CI 1.03 to 9.53, 2 trials, 414 participants). Oxamniquine 40 mg/kg compared to placebo reduced parasitological treatment failure at three months (RR 8.74, 95% CI 3.74 to 20.43, 2 trials, 82 participants). The optimal dosage of both drugs was 40 mg/kg, smaller doses being less effective and bigger doses offered no additional benefit.
The quality of the trials was unclear. Compared to placebo, praziquantel and oxamniquine were associated with a greater cure rate. In Africa, 15 mg/kg oxamniquine was less effective than 40 mg/kg praziquantel in people older than 14 years (OR 0.23, 95% CI 0.09 to 0.60), but no difference was shown using 30 mg/kg oxamniquine. In Brazil, 15 to 19 mg/kg oxamniquine was as effective as 50 to 70 mg/kg praziquantel in people older than 14 years (OR 0.61, 95% CI 0.26 to 1.46). The drugs appear safe.Comment: The quality of evidence is downgraded by imprecise results (few patients).