One and Two Doses of Oxfendazole Versus a Schedule of Two Doses of Triclabendazole in Chronic Fascioliasis

Human studies have shown that doses up to 60 mg/kg (approximately 3.6 g for a 60-kg human, which is considered the average weight of an adult in developing countries) are safe and that repeated doses of 15 mg/kg (approximately 900 mg for a 60-kg human) daily for 5 days are safe. A single dose of OXF results in significant plasma drug concentrations that reach a Cmax plateau after doses of 15 mg/kg.75 The dose to be studied in this trial is 20 mg/kg (1200 mg maximum dose), a dose only slightly higher than that achieving a Cmax plateau. This dose was conservatively selected to account for interindividual variation in plasma levels and deemed well tolerated and safe based on laboratory and ECG evaluations.

The standard of care for the treatment of fascioliasis according to the same guidelines is two 10 mg/kg doses of TCBZ 24 hours apart administered with a fat containing meal. The subjects in one of the arms of the study will receive this treatment as the standard of care. Subjects from any of the arms that fail to achieve parasitological cure will receive rescue treatment off the study with two doses of TCBZ as recommended by the Peruvian guidelines.