Trial Shows Results for Topical Treatment of Head Lice

(Centers for Disease Control and Prevention)

Topaz Pharmaceuticals Inc. in Horsham, Pennsylvania presented results of a clinical trial showing topical ivermectin cream effective at treating head lice. Findings from a related study, also presented at the recent annual meeting of the Society for Pediatric Dermatology in Portland, Oregon, showed minimal plasma absorption of ivermectin when the topical formulation was applied to children as young as six months.

Terri Meinking, President of Global Health Associates of Miami, Florida presented a poster describing a Phase-II study to establish the optimum concentration of Topaz’s ivermectin in topical cream form. The poster detailed a randomized, double-blind, dose-response study of 74 patients who received treatment with 0.15 percent, 0.25 percent, or 0.5 percent ivermectin, or vehicle (control). All ivermectin concentrations (n=51) produced a statistically significant eradication of live lice at day 15 compared to vehicle (p less than or equal to 0.003). The 0.5% concentration, now in Phase 3 studies, showed the greatest efficacy of the three concentrations studied.

Also at the meeting, Lydie Hazan, M.D., CEO of Impact Clinical Trials in Los Angeles, presented two studies in which the pharmacokinetics, safety and effectiveness of this 0.5 percent ivermectin cream were assessed in head lice-infested children. Across the studies, children aged 6 months to 10 years were enrolled, including those weighing less than 15kg (33 lbs). Ivermectin was not detected in the plasma of any of the 10 children in the first study who were sampled. In the second study, using a very sensitive test, detected levels of ivermectin were less than 1 percent of those that occur when the tablet form of ivermectin is administered. In both studies, there was a high level of elimination of head lice infestations in children treated with the 0.5 percent topical ivermectin formulation.

According to the Centers for Disease Control and Prevention, head lice (Pediculus humanus capitis) are found worldwide. In the United States, infestation with head lice is most common among preschool children attending child care, elementary school children, and the household members of infested children. An estimated 6 to 12 million infestations occur each year in the United States among children 3 to 11 years of age.