Randomized, Controlled, Assessor-Blind Clinical Trial To Assess the Efficacy of Single-versus Repeated-Dose Albendazole To Treat Ascaris lumbricoides, Trichuris trichiura,and Hookworm Infection

In many regions where soil-transmitted helminth infections are endemic, single-dose albendazole is used in mass drug administration programs to control infections. There are little data on the efficacy of the standard single-dose administration compared to that of alternative regimens. We conducted a randomized, controlled, assessor-blinded clinical trial to determine the efficacies of standard and extended albendazole treatment against soil-transmitted helminth infection in Gabon. A total of 175 children were included. Adequate cure rates and egg reduction rates above 85% were found with a single dose of albendazole for Ascaris infection, 85% ( 95% confidence interval [ CI], 73, 96) and 93.8% ( CI, 87.6, 100), respectively, while two doses were necessary for hookworm infestation ( 92% [ CI, 78, 100] and 92% [ CI, 78, 100], respectively). However, while a 3-day regimen was not sufficient to cure Trichuris ( cure rate, 83% [ CI, 73, 93]), this regimen reduced the number of eggs up to 90.6% ( CI, 83.1, 100). The rate ratios of two-and three-dose regimens compared to a single-dose treatment were 1.7 ( CI, 1.1, 2.5) and 2.1 ( CI, 1.5, 2.9) for Trichuris and 1.7 ( CI, 1.0, 2.9) and 1.7 ( CI, 1.0, 2.9) for hookworm. Albendazole was safe and well tolerated in all regimens. A singledose albendazole treatment considerably reduces Ascaris infection but has only a moderate effect on hookworm and Trichuris infections. The single-dose option may still be the preferred regimen because it balances efficacy, safety, and compliance during mass drug administration, keeping in mind that asymptomatic low-level helminth carriage may also have beneficial effects. ( This study has been registered at ClinicalTrials. gov under registration number NCT01192802.)