Engelhard Arzneimittel GmbH & Co. KG

The present study aimed to analyze the association between the prescription of ivy leaf dry extract EA 575 (licensed under the trade name Prospan® in Germany) and the incidence of antibiotic use, incident bacterial complications, and days of sick leave in adult patients with cold diseases.

This retrospective cohort study was based on the IQVIA Disease Analyzer database and included adult patients from 1032 general practices in Germany with a documentation of common cold between 2017 and 2020 (index date) and prescription of either EA 575 or an antibiotic drug within 3 days after index date. 1:1 propensity score matching based on age, sex, index month, physician, health insurance status, and the Charlson Comorbidity Index was carried out. Univariable regression models were used to investigate the association between EA 575 prescription and defined outcomes.

Data of 7034 patients treated with EA 575 and 7034 matched patients receiving an antibiotic were available. EA 575 prescription was associated with significantly lower odds of an antibiotic prescription in the time periods of 4-30 days (OR: 0.83; 95% CI: 0.72-0.96) and 31-365 days (OR: 0.44; 95% CI: 0.40-0.48) after the index date. EA 575 prescription was significantly associated with a lower rate of sick leave of more than 7 days (33.0% vs. 37.7%, OR: 0.81; 95% CI: 0.73-0.90) in patients with any sick leave, as well as with lower odds of a new cough diagnosis (OR: 0.91, 95% CI: 0.85-0.98) when compared to antibiotic prescription.

Our study provides further evidence that the use of phytopharmaceuticals, in particular ivy leaf dry extract EA 575, could contribute to a reduction in the number of inappropriate antibiotic prescriptions for respiratory infection with cough symptoms.

The results of a clinical trial published in 2016 showed the efficacy of ivy leaves dry extract EA 575versusplacebo 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.

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.

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.

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.

The functionally important switch loop of the trimeric multidrug transporter AcrB separates the access and deep drug binding pockets in every protomer. This loop, comprising 11-amino-acid residues, has been shown to be crucial for substrate transport, as drugs have to travel past the loop to reach the deep binding pocket and from there are transported outside the cell via the connected AcrA and TolC channels. It contains four symmetrically arranged glycine residues suggesting that flexibility is a key feature for pump activity. Upon combinatorial substitution of these glycine residues to proline, functional and structural asymmetry was observed. Proline substitutions on the PC1-proximal side completely abolished transport and reduced backbone flexibility of the switch loop, which adopted a conformation restricting the pathway toward the deep binding pocket. Two phenylalanine residues located adjacent to the substitution sensitive glycine residues play a role in blocking the pathway upon rigidification of the loop, since the removal of the phenyl rings from the rigid loop restores drug transport activity.