Clinical efficacy of kava extract WS® 1490 in sleep disturbances associated with anxiety disorders: Results of a multicenter, randomized, placebo-controlled, double-blind clinical trial

Background: The aim of the present trial was to investigate the efficacy and safety of kava special extract WS® 1490 in patients with sleep disturbances associated with anxiety, tension and restlessness states of non-psychotic origin. Methods: In a multicenter, randomized, double-blind clinical study, 61 patients received daily doses of 200 mg WS® 1490 or placebo over a period of 4 weeks. Efficacy was measured by the sleep questionnaire SF-B, the Hamilton Anxiety Scale (HAMA), the Bf-S self-rating scale of well-being and the Clinical Global Impressions (CGI) scale. Results: The confirmatory analysis of the two primary efficacy variables, the differences of sleep questionnaire SF-B sub-scores ‘Quality of sleep’ and ‘Recuperative effect after sleep’ after 4 weeks of double-blind treatment compared to baseline, demonstrated statistically significant group differences in favor of kava extract WS® 1490 (P=0.007 and P=0.018, respectively). Superior effects of kava extract were also present in the HAMA psychic anxiety sub-score (P=0.002). More pronounced effects with respect to the self-rating of well-being and the global clinical evaluation also indicated superior therapeutic efficacy of kava extract. Safety and tolerability were good, with no drug-related adverse events or changes in clinical or laboratory parameters. Conclusions: We conclude that sleep disturbances associated with non-psychotic anxiety disorders can be effectively and safely treated with kava extract WS® 1490.