Efficacy and tolerability of EPs 7630 tablets in patients with acute bronchitis: a randomised, double-blind, placebo-controlled dose-finding study with a herbal drug preparation from Pelargonium sidoides.

OBJECTIVE: Acute bronchitis is one of the most frequent health complaints for which patients seek medical advice. Although viral infections prevail, antibiotics are commonly prescribed. In this study, the efficacy and tolerability of EPs 7630 tablets, a herbal drug preparation from the roots of Pelargonium sidoides, were investigated in adults with acute bronchitis outside the strict indication for antibiotics. RESEARCH DESIGN AND METHODS: In this randomised, double-blind, placebo-controlled, multicentre dose-finding trial using an adaptive group-sequential design, 406 patients were randomly assigned to one of four parallel treatment groups (10 mg EPs 7630 tablets three times a day (30-mg group), 20 mg EPs 7630 tablets three times a day (60-mg group), 30 mg EPs 7630 tablets three times a day (90-mg group) or placebo three times a day) for a treatment period of 7 days. Primary endpoint was the change in the total score of bronchitis-specific symptoms (BSS) from baseline to day 7. RESULTS: Between day 0 and day 7, the mean BSS score decreased by 2.7 +/- 2.3 (placebo), 4.3 +/- 1.9 (30-mg group), 6.1 +/- 2.1 (60-mg group), and 6.3 +/- 2.0 points (90-mg group), respectively. The differences between the EPs 7630 groups and placebo were statistically significant (p < 0.0001, each). The secondary endpoints showed comparable results. EPs 7630 was well-tolerated. All documented adverse events were of mild to moderate intensity; their frequency was dose-dependent. No serious adverse events were reported. CONCLUSION: This study demonstrated statistically significant and clinically relevant superiority of all three tested dosages of EPs 7630 over placebo. All dosages of EPs 7630 were well-tolerated. Taking into account both efficacy and safety, the results of this study indicate that the 20 mg tablets of EPs 7630 taken three times daily constitute the optimal dose with respect to the benefit-risk ratio.