Efficacy and Safety of Ascending Doses of Arpraziquantel in Children Infected With Opisthorchis Viverrini

This study aims to assess the efficacy, safety and acceptability of ascending doses of arpraziquantel in children infected with Opisthorchis viverrini. The primary objective is to determine the dose-response relationship in terms of cure rate. This study will involve children aged 6-7 years, since O. viverrini infections often occur in pre-school and school-aged children, and this group is largely left untreated in current public health programs.

Inclusion Criteria: * Aged 6 to 7 years (i.e., 72 to 95 months). * Written informed consent signed by parents/caregivers (signature or thumbprint). * Agree to comply with study procedures, including provision of two stool samples at baseline and at follow-up assessment 21-28 days after treatment, respectively. * Willing to be examined by a study physician prior to treatment. * At least two slides of the quadruple Kato-Katz thick smears positive for O. viverrini. Exclusion Criteria: * Presence or signs of major systemic illness, e.g. severe anaemia (haemoglobin level of \< 80 g/L according to WHO) upon initial clinical assessment. * Known or suspected infection with Taenia solium (cysticercosis). * Known or suspected acute schistosomiasis. * Abnormal liver and kidney function. * Use of anthelminthic drugs within 4 weeks before or during study period. * Known allergy to study medications (i.e. praziquantel or any of the excipients). * Being prescribed or taking concomitantly medication with known contraindication or drug interactions with the study medication. * Concurrent participation in other clinical trials.