Efficacy and Safety of Oxantel Pamoate in Children Infected With Trichuris Trichiura

• Oxantel Pamoate (Drug): Tablets containing 250 mg oxantel pamoate
• Mebendazole (Drug): Tablets containing 500 mg mebendazole

Primary outcomes

• Cure rate (CR) of oxantel pamoate single dose compared to mebendazole T. trichiura [14-21 days after treatment]: CR will be calculated as the percentage of Trichuris trichiura egg-positive participants at baseline who become egg-negative after treatment.

Secondary outcomes

• Egg reduction rate (ERR) of oxantel pamoate single dose compared to mebendazole against T. trichiura [14-21 days after treatment]: Eggs per gram of stool (EPG) will be assessed by adding up the egg counts from the quadruplicate Kato-Katz thick smears and multiplying this number by a factor of six. Geometric and arithmetic mean egg counts will be calculated for the two treatment arms before and after treatment to assess the corresponding ERRs.
• Cure rate (CR) and egg reduction rate (ERR) of oxantel pamoate multiple doses compared to oxantel single dose against T. trichiura [14-21 days after treatment]: CR and ERR will be calculated as described in primary outcome measure and the first listed secondary outcome measure, respectively.
• Cure rate (CR) and egg reduction rate (ERR) of oxantel pamoate multiple doses compared to mebendazole against T. trichiura [14-21 days after treatment]: CR and ERR will be calculated as described in primary outcome measure and the first listed secondary outcome measure, respectively.
• Cure rates (CRs) and egg reduction rates (ERRs) of oxantel pamoate compared to mebendazole against Ascaris lumbricoides and hookworm infections in co-infected participants [14-21 days after treatment]: CR and ERR will be calculated as described in primary outcome measure and the first listed secondary outcome measure, respectively.
• Number of adverse events (AE) to assess safety and tolerability of oxantel pamoate administered as a single dose or as multiple doses, and compared with mebendazole [3 hours, 24 hours (and 48 and 72h for the multiple dose treatment arm) and 14-21 days after treatment]: Participants will be monitored at the site for 3 hours following treatment for any acute AEs. Participants will be interviewed 3 hours after treatment, as well as 24 hours after every dose received, as well as 14-21days after the last treatment dose about the occurrence of AEs. AEs will be evaluated descriptively as the difference of proportion reported AEs before and after treatment.

Sex: All, ages: 2 Years to 12 Years

Inclusion Criteria:

* Aged between 2 and 12 years.
* Written informed consent signed by parents/caregivers (signature or thumbprint) and, for children aged 6-12 years, written assent from the child.
* Agree to comply with study procedures, including provision of two stool samples at the baseline and at follow-up assessment 14-21 days after treatment, respectively.
* At least two out of four Kato-Katz thick smears positive for T. trichiura at baseline.
* Willing to be examined by a study physician prior to treatment.

Exclusion Criteria:

* Presence or signs of major systemic illness or abnormal physical findings at screening, e.g. severe anaemia (Hb level <80 g/L according to WHO) upon initial clinical assessment.
* Known allergy to study medication (i.e. oxantel pamoate, mebendazole or any of the excipients).
* Use of anthelminthic drugs within 4 weeks before or during study period.
* Being prescribed or taking concomitantly medication with known contraindication or drug interactions with the study medication.
* Actively participating in other clinical trials during the study.
* Pregnancy (female participants that report to have reached menarche

• Results publication: Jeanguenat H, Schnoz A, Amour AK, Ahmada AA, Seif SN, Mohammed IS, Hattendorf J, Ali SM, Keiser J. Efficacy, safety, and acceptability of a child-friendly, chewable formulation of oxantel pamoate versus mebendazole for Trichuris spp infections in children aged 2-12 years in Tanzania: a randomised, single-blind, phase 2 trial. Lancet Infect Dis. 2026 Jul 22:S1473-3099(26)00238-0. doi: 10.1016/S1473-3099(26)00238-0. Online ahead of print. PMID 42486129

• Jennifer Keiser, PhD, Study chair, Swiss Tropical & Public Health Institute