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.
Jeanguenat Hannah H, Schnoz Annina A, Amour Amour Khamis AK, Ahmada Ahmada Ali AA et al.
Trichuriasis, caused by the nematodes Trichuris trichiura and Trichuris incognita, affects an estimated 267 million people worldwide, particularly children. Currently available treatments (albendazole and mebendazole) fail to achieve sufficient cure rates. Oxantel pamoate is a drug known for its trichuricidal activity. In this study, we aimed to assess whether a newly developed, child-friendly oxantel pamoate formulation is superior to mebendazole, one of WHO's recommended treatments for trichuriasis. We conducted a randomised, single-blind, phase 2 trial in a primary school and nursery on Pemba Island, Tanzania. Children aged 2-12 years diagnosed with Trichuris spp infection were randomly assigned to receive single-dose oxantel pamoate (20 mg/kg bodyweight as chewable 250 mg tablets), multiple-dose oxantel pamoate (20 mg/kg bodyweight as chewable 250 mg tablets on 3 consecutive days), or single-dose mebendazole (500 mg as one chewable tablet). Participants were randomly assigned in a 1:1:1 ratio by use of a computer-generated randomisation code stratified by baseline infection intensity and age. Participants, study physicians, and laboratory technicians were masked to treatment allocation; no placebo treatment was added to match procedures across groups. The primary endpoint was the cure rate, assessed by Kato-Katz 14-21 days after treatment, and a secondary endpoint was egg reduction rate, assessed in the available case population (all randomly assigned participants who provided any follow-up efficacy data). Safety analysis included all randomly assigned participants who received at least one dose of study treatment. The trial is registered at ClinicalTrials.gov (NCT06720259) and is completed. Between April 16 and May 28, 2025, we recruited 166 participants, of whom 163 were randomly assigned to treatment groups (81 female, 82 male). Of these, 55 received single-dose oxantel pamoate, 54 multiple-dose oxantel pamoate, and 54 single-dose mebendazole; one participant in the multiple-dose oxantel pamoate group was lost to follow-up. The cure rates were 18·2% (95% CI 9·1-30·9) for the single-dose oxantel pamoate group, 64·2% (49·8-76·9) for multiple-dose oxantel pamoate, and 7·4% (2·1-17·9) for single-dose mebendazole. Logistic regression showed that single-dose oxantel pamoate was not significantly superior to single-dose mebendazole in terms of cure rate (odds ratio 0·36, 95% CI 0·09-1·16; p=0·10). However, the egg reduction rate was superior for single-dose oxantel pamoate compared with mebendazole (a difference of 10·0 percentage points [95% CI 2·5-21·3] between 96·2% [93·0-98·1] and 86·3% [75·0-92·9], respectively). Oxantel pamoate was well tolerated, with abdominal pain reported as the main adverse event. Our study did not provide sufficient evidence of superiority in terms of cure rate for single-dose oxantel pamoate over single-dose mebendazole. However, the superiority in egg reduction rates seems to corroborate the higher efficacy observed in previous phase 2 studies and supports phase 3 development towards regulatory approval. European Union. For the Swahili translation of the abstract see Supplementary Materials section.