Abstract
INTRODUCTION: The results of a clinical trial published in 2016 showed the efficacy of ivy leaves dry extract EA 575 versus placebo in the treatment of patients suffering from acute cough. A clinical trial with a very similar design was conducted to not only show the reproducibility of former results but also to investigate an alternative dosing scheme. METHODS: This randomised, placebo-controlled, multicentre, double-blind clinical trial was conducted to assess the efficacy and safety of a liquid containing EA 575 in the treatment of acute bronchitis. A total of 209 patients were treated with a liquid containing EA 575 as an active investigational medicinal product (verum) either two (7.5 mL) or three (5 mL) times a day or placebo in the respective dosing scheme for 1 week, with a total observational period of 2 weeks. The primary efficacy outcome was a change in Bronchitis Severity Score (BSS) of the pooled placebo and pooled verum groups between visits 1 and 5. Additional secondary parameters were assessed, including, for example, change in cough severity as assessed by a visual analogue scale (VAS) and the Verbal Category Descriptive (VCD) score. RESULTS: Superiority of verum over placebo was during and at the end of treatment, as measured by BSS. No significant differences between the dosing schemes were observed. VCD scores and VAS measurements also showed the superiority of verum over placebo. CONCLUSION: The existing data on the clinical efficacy of EA 575 were confirmed. Furthermore, a new dosing scheme was shown to be noninferior to the currently used scheme while maintaining the safety and tolerability of the well-established cough liquid containing EA 575.