A Phase 2 interventional study of Apraziquantel in Opisthorchis Viverrini, sponsored by Jennifer Keiser. Recruiting at 1 site in Laos. Open to participants aged 6 Years to 7 Years. Per ClinicalTrials.gov, last updated 2026-08-04.
Sponsored by Jennifer Keiser · Phase 2, Interventional, and Treatment
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.
Jennifer Keiser is the lead sponsor of 17 studies on the registry; 3 are open to participants now.
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Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
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The protein in red blood cells that carries oxygen. A low level is anaemia, which can cause tiredness and breathlessness. Measured in g/dL or g/L (9 g/dL is 90 g/L).
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Informed consent
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Hemoglobin (Hb)
The protein in red blood cells that carries oxygen. A low level is anaemia, which can cause tiredness and breathlessness. Measured in g/dL or g/L (9 g/dL is 90 g/L).
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Excipients
The other ingredients in a medicine besides the active drug, such as fillers, colours or preservatives.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Contraindication
A reason a treatment, test or procedure should not be given to a particular person, such as an allergy, another illness or a medicine they take.
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Treatment with a single dose arpraziquantel: 30 mg/kg, orally administered
Drug: Apraziquantel
Treatment with a single dose arpraziquantel: 40 mg/kg, orally administered
Drug: Apraziquantel
Treatment with a single dose arpraziquantel: 50 mg/kg, orally administered
Drug: Apraziquantel
Treatment with a single dose arpraziquantel: 60 mg/kg, orally administered
Drug: Apraziquantel
Treatment with a single dose arpraziquantel: 20 mg/kg, orally administered
Drug: Apraziquantel
Tablets (dispersible) containing 150 mg arpraziquantel
Cure rate (CR) of arpraziquantel against O. viverrini
CRs will be calculated as the percentage of O. viverrini egg-positive participants at baseline who become egg-negative after treatment.
Time frame: 21-28 days after treatment
Egg reduction rates (ERR) of arpraziquantel against O. viverrini
Eggs per gram of stool (EPG) will be assessed by calculating the mean egg counts from the quadruplicate Kato-Katz thick smears and multiplying this number by a factor of 24. Geometric and arithmetic mean egg counts will be calculated for the different treatment arms before and after treatment to assess the corresponding ERRs.
Time frame: 21-28 days after treatment
Safety and tolerability of the different arpraziquantel dosing regimens, and compared to placebo
Participants will be monitored at the site for 3 hours following treatment for any acute adverse events (AEs). Participants will be interviewed 3 hours and 24 hours after treatment, as well as 21-28 days and 42 days after treatment administration about the occurrence of AEs. AEs will be evaluated descriptively as the difference of proportion reported AEs before and after treatment.
Time frame: 3 hours, 24 hours, 21-28 days and 42 days after treatment
Plan to share: No
No publications or documents are linked to this record.
Started Jul 2026 (actual). Primary completion is estimated for Oct 2026, 3 months after the start.
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Jennifer Keiser