The efficacy and tolerability of triclabendazole in Cuban patients with latent and chronic Fasciola hepatica infection

Current chemotherapy for the treatment of infections caused by the liver fluke Fasciola hepatica is not satisfactory. Therefore, the efficacy and tolerability of triclabendazole (TCZ) was assessed for this indication. Eighty-two patients (51 female, 31 male, age 15-81 yr, mean 42 yr) with chronic or latent F. hepatica infection refractory to previous anti-helminthic chemotherapy were enrolled in a 60-day open, non-comparative trial. Patients received 20 mg/kg TCZ as two doses of 10 mg/kg administered after food 12 hr apart. Efficacy of treatment was assessed by stool microscopy, determination of Fasciola excretory-secretory antigen (FES) in feces, and by ultrasonography (US) which were systematically performed pre-therapy and on Days 1-7, 15, 30, and 60 post-therapy. For continuous safety assessment, patients were hospitalized during the first week after therapy and then monitored at home for the appearance of any adverse events. Clinical chemistry and hematology tests were carried out on Days 1, 3, 7, 15, and 60, and whenever an adverse effect occurred possibly related to therapy. Seventy-one (92.2%) of the 77 patients who completed the 60-day follow-up period became egg-negative. Efficacy of therapy was supported by the disappearance or decrease of FES antigen and of ultrasonography abnormalities. In the 6 remaining patients, parasitological cure was achieved by another single TCZ dose of 10 mg/kg on Day 60. A total of 74 adverse events possibly related to therapy was reported by 54 patients. The most important adverse event was colic-like abdominal pain (40 patients [49%]) consistent with the expulsion of the parasite through the bile ducts as confirmed by US on Days 2-7. Most adverse events (53) were graded as mild, 20 as moderate, and only 1 as severe (a biliary colic responding to spasmolytic therapy within two hours). Triclabendazole 20 mg/kg is an effective therapy for the treatment of F. hepatica infection in patients who have failed to respond to other antihelminthic agents. Biliary colics reflecting the expulsion of dead or damaged parasites usually occur during Day 3-7 and respond well to spasmolytic therapy.