High efficacy of a dimeticone-based pediculicide following a brief application: in vitro assays and randomized controlled investigator-blinded clinical trial.

BACKGROUND: Increasing resistance of head lice against neurotoxic agents and safety concerns have led to the search for treatment alternatives. Dimeticones with a physical mode of action are safe, and bear a reduced risk for the development of resistance. METHODS: We performed in vitro bioassays to assess pediculicidal and ovicidal activities of a new dimeticone-based product, and a randomized controlled clinical trial to assess efficacy, following 10 min application. Of 153 individuals screened, 100 participants with active head louse infestations were randomly assigned to treatment with either a dimeticone-based test product, or a 0.5% permethrin-based reference product (50 participants per group). Participants received two topical applications of either the test (10 min) or reference products (45 min) at days 0 and 7 or 8. Outcome measures included the efficacies of treatment and their safety, as well as global and local tolerability at baseline, and days 1, 7, and 10. RESULTS: After 10 min exposure, all lice treated with the dimeticone test product were classified as non-viable in the in vitro assay. Ovicidal activity after treatment of eggs with the dimeticone test product was 96.8%. In the clinical trial, 96 patients completed all study visits. In the full analysis set (FAS) population, on day 1 after one application, 98% of patients were cured in the test group, as compared to 84% cured in the reference group. All participants in both groups were free of head lice on day 10, following two applications (100% cure rate). In total, 42 adverse events (AEs) in 23 patients of both treatment groups were recorded, with the majority of AEs classified as mild. CONCLUSIONS: We have shown a high level of pediculicidal and ovicidal activity, and clinical efficacy and safety, of a brief application of a new dimeticone-based product. The short application time and reduced risk for the development of resistance are key drivers for improved patients' compliance. TRIAL REGISTRATION: EU Clinical Trials Register EudraCT  2016-004635-20 . Registered 14 November 2016.

Efficacy and Safety of a Mineral Oil-Based Head Lice Shampoo: A Randomized, Controlled, Investigator-Blinded, Comparative Study.

BACKGROUND: Due to increased resistance and safety concerns with insecticide-based pediculicides, there is growing demand for head lice treatments with a physical mode of action. Certain mineral oils kill lice by blocking spiracles or by disrupting the epicuticular wax layer. The present study was performed to evaluate efficacy and safety of a mineral oil-based shampoo. METHODS: This randomized, controlled, investigator-blinded, monocentric study (EudraCT registration no. 2014-002918-23) was performed from October 2014-June 2015 in Germany. A mineral oil shampoo (Mosquito® Med Läuse Shampoo 10 in Germany, Paranix or Silcap shampoo elsewhere), registered as medical device, was compared to a conventional, locally reimbursed, pyrethroid-based pediculicide (Goldgeist® Forte solution). In total, 107 patients (>1 year) with confirmed head lice infestation were included (test arm: n = 53; control arm: n = 54). All subjects received two applications of either test or control product at day 0 and day 7, according to the instructions for use. Efficacy and safety was evaluated directly, 1h and 24h after first application, before and after second treatment, and at day 10. The main objective was demonstrating a cure rate for the test product, being superior to 70% at day 10. RESULTS: Cure rates at day 10 (corrected for re-infestation) for the test product (96.1%) and control (94%) significantly exceeded the pre-defined target (70%) (p < 0.001, 2-sided, 1-sample, chi-square test) with confirmed non-inferiority for the test product. Over all visits, cure rates were consistently higher for the test product, whereas more initially-cured subjects remained lice-free until end of study (78%; control: 60%). Both products were safe and well tolerated, offering good esthetical effects. CONCLUSION: This study showed that substance-based medical devices (including the tested mineral oil shampoo) can be safe and effective alternatives for insecticide-based pediculicides, with less risk for development of resistance because of the physical mode of action. TRIAL REGISTRATION: German Clinical Trials Register (DRKS) DRKS00009753 and EudraCT database 2014-002918-23.